The German army gets rid of Hitler and the Nazis (at least the most extreme supporters of Hitler) and his racist policies.
So we have a military junta neo-Wilhelmine government supported by conservative public opinion. Such a government would still strongly support a claims on the 1914 territories and if necessary war against Poland, but not at the risk of fighting the Western Powers, nor they would support anything like Barbarossa.
Therefore, let's assume that Britain, pleased with the overthrow of Hitler, is somewhat more willing to compromise about German claims. A Munich-II conference happens, where Poland is strongarmed in returning Danzig, West Prussia (minus Gdynia and a extraterritorial land connection to it) and Upper Silesia to Germany, and Germany signs a treaty of non-aggression with Poland and garantees its boundaries. There is an heartfelt Anglo-German detente. Breakneck rearmement is slowed, and the economy stabilized. The German people is pleased with the new government. Traditonal parties (minus the Nazis and the Commies), civil and poltiical rights, and the Landers are restored. The generals implement a revision of the Weimar constitution that bans "extremist" (Nazis and Communists) parties, greately strenghtens the executive, and restores the monarchy. Louis Ferdinand is crowned as Kaiser. The new elections see a coalition between the conservative-nationalists and the center party seize the power. The Protectorate of Bohemia-Moravia is formally annexed but given a special autonomy statute. The Motolov-Ribbentrop Pact is denounced or never signed in the first place. Pleased with the Polish gains, the new German government focuses on building a sphere of influence in Eastern Europe by peaceful means, and anti-Soviet containment.
Stalin gets into high alarm as he sees his fears of an anti-Communist front take shape, and goes into preemptive expansionism mode. Plans for invasion of the Baltic countries, Finland, and Romania are prepared, and Communist parties worldwide are ordered to abandon "popular front" anti-fascist cooperation and step up anti-capitalist sabotage.
Mussolini gnashes his teeth as he sees his opportunity to rebuild the Roman Empire by opportunist explotiment of Nazist might. He reviews the map of Europe seeking for alternative targets for expansion.
The invasion of Poland never happens so World War 2 never happens instead Germany intervenes in the Baltic states and Finland “saving” then from the Soviet Union.
The Soviet Union on the other hand gets cheeked in Finland and the Baltic so never gets Moldavia and Besarabia at all.
Very Unlikely. Sooner or later, Stalin would feel sufficiently confident in the Red Army's buildup and paranoid about the intentions of Germany and the Western Powers, as to risk a major preemptive attack in 1941-43. You still get a WWII without Hitler, but it is Britain, Germany, and France vs. the USSR.
Either in 1941-43 when Stalin unleashes his big Reverse Barbarossa on Europe, if he gets cold feet in 1939 and scaps plans about Baltic, Finland, and Romania. If he does not, because he believes he can get away with some land-grabbing, from Germany focused on internal readjustment and the Western Powers being spineless pacifists that never stood up to Hitler, he invades the Baltic countries, Finland, and Romania. London, Paris, and Berlin make an hasty alliance, and you have WWII in 1939-40. All countries are still rather unprepared for such a major war at this stage, so it mostly bogs down in a stalemate in Finland, Romania, and Eastern Poland, until Fall 1940 or Spring 1941.
Or alternatively, Stalin dares not make moves on Finland, Lithuania, and Romania, or he does but backs down from the other Great Powers' opposition (probably he gets away with annexing Estonia and Latvia). So he seethes down and concentrates on building up his Great Red Army for a general offensive in 1941-43. A cold war ensues in Europe between the Soviets and the Anglo-Germans.
Hungary and Rumania go to war over their border disputes in Transylvania. Germany stays neutral and so does Italy. Rumania gets most of the support from Yugoslavia and France. The border remains the same (same small changes).
If the USSR has not attacked, quite possibly. No, Germany would support its main ally in Eastern Europe, and so would Italy. A situation much like the SCW would ensue (Hungary as the German-italian proxy, Romania as the French proxy), except most likely Stalin threatens to backstab Romania and Bucharest loses the war. Romania is cut down to size as it loses Transylvania to Hungary and Bessarabia to the USSR. Much like OTL. Romania either sinks into isolationism or becomes a cowed German satellite. Buffed-up Hungary might annex Slovakia.
Italy invades Albania and then Greece.
Albania has been already annexed by Italy. Again, only if WWII has not broken out, otherwise Il Duce goes to be an happy member of the anti-Communist crusade, after having been promised by London and Berlin future compensations in the Balkans and some Soviet booty if he does not messes up with the rearguard of the coalition.
Otherwise, there is 50%-50% probability of him attacking Yugoslavia or Greece first.
Germany helps Italy with 1 division of mountain troops and the German Air force gives air support.
Depends on how much friendly relations between London and Berlin are at this point. if they are in full detente, doubtful Germany would risk to anger Britain by committing troops, although they might send a lot of support. Without German "volunteers" it is entirely likely that the Italian attack would fail, as IOTL, albeit here Musso can focus all the military strength of Italy on one objective, so he might well succeed, he has not another front in Africa.
However, Italy has far better chances to succeed if the sequence is reversed, attack Yugoslavia first. Italy has a boundary, the terrain is less daunting, can get support from Hungary and Bulgaria, as well as an extensive net of Croat insurgents that Italy has been cultivating for some years. And Britain cares far less for Yugoslaiva, which was a French creation, than for Greece.
Italy gets northern Greece and attaches it to the Albanian Kingdom who is an Italian protectorate. France and Great Brittan support Greece but short of sending troops. A referendum organized by the Italians and observed by France, Great Britain and Germany shows that a majority of the population in northern Greece supports “unification” with Albania (there was a substantial Albania minority in northern Greece at this time). Italy guarantees Greece that there will be no more territorial demand on Greece and the Albanian problem have been resolved.
Depends on how willing France and Britain are willing to appease Italy for the sake of anti-Soviet committment, and again how friendly are the relationships between Italy, Germany, and Britain. There were British garantees on Greece since 1939 as well. Otherwise, if Italy botches the attack as IOTL or Britain threatens intervention and Germany does not support Italy, Mussolini may be forced to an humiliating retreat. Depending how much humuliating, he may face a coup. If everything aligns favourably for Italy, it might well get away with the annexation of Southern Epirus (the only part of Greece with a sizable Albanian minority. I suppose you refer to that by "northern Greece". BTW, Albania was not a protectorate, it had been annexed (Vittorio Emanuele III got the title of King of Albania).
Now Italy turns it eye on Yugoslavia and together with Hungary, Bulgaria, and Germany to a small extent and of course the Kingdom of Albania ( which is an Italian protectorate) dismembers Yugoslavia.
As I said above, rather better chances of success if Italy tries this first. Same considerations as for Greece, above. But if it is a gangbang on Yugoslavia by several nations, and there is serious Croat insurgency, London might well earmark Yugoslavia as a lost cause. Better to organize a Croat insurgency, and set up some kind of border incident, as a casus belli. Britain is not that much interested inYugoslavia, France is but is not going to act without London, so this might well work.
Again a referendum is held and the territories of Kosovo, northern and southern Macedonia, and Montenegro decide to unite with the Kingdom of Albania.
The eastern part of Macedonia and Serbia go to Bulgaria. Vojvodina goes to Hungary. Dalmatia becomes an Italian province and Germany gets most of Slovenia, the rest of the country is divided between Croatia and Serbia (2 puppet states under the influence of both Rome and Berlin).
Dalmatia, Kosovo, and Montenegro go to Italy, all Macedonia to Bulgaria, Vojvodina to Hungary, Slovenia to Germany, Croatia with Bosnia becomes a Italian-German puppet. Serbia is beaten down. It might become a nominal Axis puppet as well, but it is an hotbed of nationalist resentment and Communist subversion. In short order, it might switch to be a puppet of the USSR.
All this is archived through small wars and diplomacy, France and Great Brittan never go to war against Germany and Italy because they see the Soviet Union of the biggest threat to their security. Also the Italian propaganda machine uses the fact that both Greece and Yugoslavia have Albania minorities in abundance to keep the international public opinion who is “outraged by the Greek and Serb atrocities towards the Albanians” (some of which in reality really happened) neutral and in some cases even sympathetic to the case of small nations “the Kingdom of Albania”.
It might or it might not work. It essentially depends on whether Britain are sufficiently committed to anti-Soviet committment (otherwise Mussolini suffers an humiliating military or diploatic defeat, and may fall from power, in such a case a moderate conservative-autoritarian military government takes his place). Italian propaganda could and would harp on the Serb misdeeds towards the Albanian and Croat minorities alike. There were extensive links between fascist Italy and Croat separatism.
France is going to gnash their teeth seeing all their old allies (Yugoslavia, Romania, Czechoslovakia, Poland) crumble. Hopefully, this might likely push them to a rightist takeover and some much-needed reforms, instead of isolationism or doing something really stupid (like breaking the alliance with Britain and making one with Stalin).
The Italians and the Germans came out of this small wars and intervention stronger and as the defender of freedom. With their appetite for conquest and wars satisfied Germany and Italy feel that the wrong done by the Versailles Treaty has been reversed and now they are ready to join the rest of the great powers as equals.
Good for them, since Europe is going to get the trial of their generation when the Soviet jaggernaut, armed to the teeth, attacks in 1941-43. However, after much bloodshed, Stalin is overthrown when the Anglo-Germans, hopefully with help from Italy and France, and American financial support, gradually cut down the Red Army until the Soviet strategic reserve is exausted. As long as either Hitler and Stalin are around, you cannot avoid WWII. However, with a moderate neo-Imperial Germany, and Mussolini not being to make too much trouble by hinself, TTL may see a rather happier outcome to WWII, as all of Europe is restored to a decent regime as Stalin is overthrown.
In this Alt-WWII, Europe also fares better because Western Europe and Germany are preserved from destruction, albeit Eastern Europe and Russia shall be absolutely wrecked. Even more so if, as it is likely, Britain and Germany build the nukes by joint effort and use them to crush Soviet resistance for good. If WWII explodes in 1939-40, quite possibly the Allies crush Stalin before developing the bomb, but if the war erupts in 1941-43, they could develop nukes in the latter phase of the war. if Britain and the USSR are at war, most likely Communist spies in the British nuclear program are caught early, and without their leakage, the Soviet nuclear program is delayed well into the 1950s. This bodes ill for Soviet cities...
However, there is still Yamato Japan around to no good...