When the Entente declared war on Germany and had begun launching bomber raids within a weak Moscow panicked. The last time a Russo-German alliance tried to take on the Entente it did not go well, and even though the balance of power in Southern Europe had changed significantly the cautious government of the Worker's Federation decided to slide into a 'wait and see' approach. If Germany won then their treaty rights to the Baltic would remain respected. If Germany lost then they could probably get away with handing back their little slice of Poland without a war.
The Entente mobilised their armies digging in defenses along the French and Belgian borders. Italy launched a few light raids in the Alps to distract the French. The Portugese and Spanish armies clashed lightly in border skirmishes, but for a full 2 months both sides sat cautiously eyeing the other. Then the Germans surprised the world with a mass invasion of the Netherlands. The Dutch army was rapidly overwhelmed and forced to surrender as the Royal Family evacuated, allowing the Germans to sweep behind the Entente lines, grabbing Antwerp and Brussels before Entente forces could turn to stop them. The Entente were left stumbling on a back foot for the entire autumn of 1936. By the start of December German forces broke into the outer suburbs of Paris. With winter setting in French, British, and German forces began to dig in. Both sides had supply line issues which had left winter clothing in short supply, and an Italian invasion of Libya as well as fighting against the Arab Republic needed immediate attention. January of 1937 would see the arrival of another Entente power which had no concerns about fighting in the winters of France, their opinion of the weather summed up with the question "C'est ou l'hiver?". The Canadians launched a significant offensive north of Paris, pushing to Amiens throughout the winter.
The spring of 1937 would see a new wave of violence though. Canadian forces were pushed back by a massive German counter attack in early April and German forces reached the Seine river at a number of points. Desperate Entente forces acepted offers from Norway, Latvia, and Estonia to base aerial raids in those nations, hoping that the move would avoid drawing the Worker's Federation into the war. Berlin was outraged and with Swedish assistance invaded both Denmark and Norway to cut off Entente access. The Worker's Federation protested what effectively amounted to a closing of the Baltic as the Germans established minefields to keep Entente naval forces away from the area, but the protests fell on deaf ears. The Entente however saw it as a gap that they could wedge open. Realising that raids on northern Germany or Sweden were incredibly risky the Entente nonetheless increased these raids, both hoping to disrupt supply lines in Germany and that a German invasion of the Baltics would further outrage Moscow (the Entente had no knowledge of Germany promising the area to Moscow, they merely hoped a longer border would increase tensions). Lithuania began to protest, but Latvia and Estonia hoped Neutral Lithuania would prove an effective buffer. When Spain won a surprising victory against Portugal at Braganca and broke the Portugese line however the Ravenna accord was forced into a need to save face.
Throwing more men into Northern France would only further clog the battle lines there (1.5 million Germans and 1.2 million Entente forces were crowded into Paris and it's suburbs alone) German and Italian forces agreed to support their Balklan allies' desires and launched an invasion of Yugoslavia, Romania, and the Ottoman hearltand during the summer of 1937. The Entente sent what forces they could, but were stretched quite thin. Bombing campaigns increased with a series of 200 bomber raids striking Berlin. Germany could no longer tolerate the pro-Entente Baltic states, and when an outraged letter to Moscow that they 'had best invade the Baltics or the treaties might be rendered void' was answered with a letter more or less stating 'we're looking into the matter' the Germany military government decided the communists of the Woker's Federation were incompetent and invaded Lithuania, rolling into southern Latvia within 3 weeks.
The Worker's Federation threw a number of ultimatums at Berlin, all of which were dismissed as empty threats. In September of 1937, as German forces captured Riga, the Worker's Federation declared war. Berlin was marginally surprised, but expected the Worker's Federation's trademark indecisiveness to result in an easy and quick victory, while Stockholm rejoiced at the opportunity to liberate Finnish Swedes who had frequently been imprisoned or relocated by a paranoid Helsinki. German forces headed towards Talinn were redirected towards Leningrad, though the advance was cautious as winter supplies were shipped ahead to avoid a repeat of the slowdown in Paris a year ealier. Forces heading in the Ukraine were likewise cautious and well supplied. WF forces meanwhile were typically poorly equipped, though the officer core was a well trained and loyal force.
As the Entente celebrated their luck that Germany now had a second front and fighting in Paris was letting up news hit from China. The Xenophobic Dignity League had launched a massive offensive against Republican forces. The Dignity League had been stockpiling supplies for some time, and increased efforts when war broke out in Europe, while border raids had slowly eaten into Republican material. Now millions of hyper-nationalist soldiers were swarming towards the coast and the Entente had limited resources in the East to fight them. Japan and Korea sent whatever men they had ready (with most of their regular forces fighting in the Middle East the Japanese were caught off guard) while the UK attempted to mobilise a reluctant India (the population had grown unhappy about delays in improved equality between Indians and Whites). As German forces advanced towards Minsk and dug in for winter the Dignity League overran Beijing.
1938 saw a slow push in France that gradually forced the German line back, but at the cost of roughly a million men. Meanwhile the Ottoman Empire effectively collapsed, WF or British forces having to prop up the few remaining generals still willing to fight. Southern Republican China completely collapsed to the League forces, and the new Oriental Dignity League (ODL) was formed with the invasion of Vietnam. ODL forces were not particularly well equipped or trained by the standards of the day, but neither were their opponents. The most industrialised Asian power, Japan, had invested little in her military due to the pacificistic streak of the Anarchist governments that dominated the early 1930s. Meanwhile the ODL could call upon untold millions of men, radicalised into a fanatical devotion to the ideals of the League (that China was the source of all civilization and that all other nations had grown corrupted in need of purging). The German military was able to besiege Moscow by October, and many expected the eastern front to soon collapse.
As winter set in the Communists launched a number of counter attacks, which the Germans had done little to prepare for, expecting a repeat of the assaults the winter before, where half frozen Russians had struggled with barely functional aircraft and vehicles (German vehicles suffered similarly in the cold, but the difference in training, food supplies, and small arms left the Germans with an edge). These assaults would be very different though. In the ports of the Russian far north and Pacific during the earlier summer industrial supplies and blueprints had begun landing, along with engineers. Canada had just engaged in a crashcourse militarisation of her own industrial sector and had plenty of experience building aircraft and other vehicles to function in winter temperatures. While the summer of 1938 proved exceptional stressful for both parties (Eurasians pressured to build in weeks factories that normally took months and learn assembly line jobs at a similar breakneck speed while Canadians had to force their way through the Worker's Federation's cautious buraucracy and secret police) the upgraded factories, new factories, and massive quanities of trucks imported from Canada (OTL Canada built ~800K trucks with 11 million people, the US ~2.3 million with 130 million, so clearly Canada likes trucks) made a significant difference in the winter offensive of 1938/1939. With the Germans pushed back significantly by temporary Russian aerial superiority and improved logistics Moscow suddenly had breathing room.
While German counter offensives in spring would stabilise the front and it would descend into an unclear tit for tat that cost roughly a million lives on each side it saved the Worker's Federation from an existential crisis and opended the opportunity to deploy troops against the ODL in Mongolia and East Turkistan while increasing forces in Anatolia. The French Front would prove similarly bloody and indecisive, the limited amount of tanks available was quite effectively balanced by anti-tank rifles and similar defenses (tanks were never really a thing in the Moroccan War, so tank development is a fair bit behind OTL). The biggest change that occured was the ODL's invasion of Burma, as the better part of a million Chinese soldiers poured into Burma, finally bringing the war to India. The Indian populace may have had little love for London, but fear of the ODL's reported war crimes in occupied territories was clearly the greater evil. Hundreds of thousands began volunteering across India.
Of course that is only covering the two closely tied wars, that of Europe and that of Asia. The Triple War had a third theatre that deserves discussion. The election of President Moore had prompted protest, and occasionally even militia activities in rural regions by both socialist groups and occasionally apolitical members of ethnicities Moore had slandered. Moore was easily able to turn these outbursts into a victory thought, declaring that these groups were 'finally showing their true colours'. Both the Republicans and Democrats were easily swayed to the idea of banning the Socialist Party, Communist Party, and Democratic Communist Party in surprisingly short order for a normally gridlocked government. The two parties hoped swift action would show the public that the two parties still functioned when necessary, but the NaCos were able to spin it as their guiding hand finally allowing decisive action. Moore's push to begin mass arrests of Finnish and Slavic men ("natural communists" as he called them) stalled however, neither of the old parties agreeing with that step. Many of Moore's economic and security initiatives also failed, declared to radical by the old parties, which pro-NaCo pamplhets and newspapers decried. When, in 1938, an apparently Finnish communist made an attempt on Moore's life, shooting the President in the army and killing the Republican Vice President, the results in the following mid-terms were decisive, people were tired of far left terrorism that had rocked the nation and supported Moore's hard line response. (There exists some evidence that the rampant terrorism was in part aided, or even occasionally conducted by NaCo militia groups, and many will insist the assasination attempt worked out too cleanly to have been genuine though no good evidence exists to prove it was a false flag operation.) The NaCos were able to take control of the Senate as well, with John Polzul being stationed as Senate Speaker.
Still the United States seemed shakey in the winter of 1939, and with uncertainty about how the NaCo's might renegotiate their relationship with Costa Rica certain elements of that nations army felt they were better off siding with the Latin league . A coup on January 28th was mostly successful (some loyalists escaped into the countryside) and the new Costa Rican government applied to join the Latin League. The were quickly accepted, filling the gap between the north and south of the League. Moore however was not about to take the loss of the United States' only real ally lightly, and quickly sent a letter that read to Mexico and Bogata as an ultimatum. Not realising the degree to which the Republicans and Democrats were prepared to grind their heals in to stop anything passing congress (especially not a declaration of war) the Latin League panicked. Hoping to take advantage of the United State's rather small peace time army and avoid a long war the Latin League decided to launch an offensive while the US mobilised, hopinh that capturing Los Angeles and most of Lincoln (West Texas) could bring the USA to the negotiating table. We shall see how that goes.