Have Germany attack the USSR before they go up against the Western Allies. In 1939, the USSR is still ultra-weak and reeling from the failure of the five year plan, the Holodomor, and Stalinist purges. If Hitler wasn't so aggressive towards the West during the 1930's and had used the USSR's ambitions for Poland and the Baltics as evidence of impending Soviet imperialism, he could have rallied the international community to crush the USSR. Everyone hated the USSR at that point, and if Hitler promised to provide most of the troops for the invasion, I think that the Western Allies would have agreed to not intervene (worst case scenario) or to help out with supplies (best case scenario). The way I see it is Hitler telling Japan that it would be best for both of them to focus on taking down the USSR, the USSR getting taken down by a coalition of countries who have little in common besides their passionate hatred of communism, and then both Hitler and Japan continuing with their IOTL expansion plans.
Hitler proceeds to push for Poland and start the war with the Western Allies while the Japanese proceed to invade China without overextending themselves too much. If Hitler performs his continental plan (going from the Invasion of Poland to the Fall of France) exactly as IOTL without subsequently attempting Operation Sea Lion (which was doomed to be a failure), he can then devote most of his troops to knocking the British out of North Africa and getting more countries to join the Axis Powers (most neutral countries would have joined the Axis immediately since they want to be on the winning side). Meanwhile, the Japanese (having built up their army instead of their navy due to the initial Soviet invasion plan) have a much stronger land force and manage to grab and hold much more of China than just the IOTL coastal areas. With this connection through mainland China being secure, the Japanese invade Southeast Asia and the European concessions in China through the mainland (no need to conquer the Philippines and bring America into the war!), successfully bringing the area under their rule (with Thailand joining the Axis like IOTL). The Japanese also invade the various European-owned Pacific Islands (an ultra-powerful Navy wasn't needed to grab those).
At this time, the Allies lose North Africa thanks to Rommel having a lot more men and supplies (no diversions to the USSR!), causing France to lose its empire in Africa (most of which was concentrated in North and West Africa) and Britain to be isolated from its Asian colonies due to the loss of the Suez Canal. France, having been deprived of its Euro-African territories by Germany/Italy and its Asian/Pacific territories by Japan, will most likely surrender right about then; along with all of the governments in exile (who will realize that they are a lost cause and that German dominance of Europe and Japanese dominance of Asia is there to stay). Germany can then focus its efforts on conquering as much of Africa as possible, encouraging pro-Nazi movements in Ireland, and getting the Muslim nations of the Middle East and Central Asia to invade Britain's colonial holdings in the area.
Japan, meanwhile, can then focus on finishing the conquest of China (with German assistance in Tibet and Xinjiang), taking the remaining European territories in the Pacific (Dutch East Indies, Australia, New Zealand, etc.), and invading British India with the help of nationalistic rebels in the Raj as well as pro-Axis Iran and Afghanistan. Provided that they keep their diplomatic alliances secure (good diplomats are just as important to the war effort as good generals, as the Bismarck-Moltke partnership clearly showed) and avoid provoking the United States NO MATTER WHAT (it is literally better to lose a thousand men and a ton of supplies than to give the Americans an excuse to enter the war on Britain's side). At some point, Britain would have realized that a peace treaty is the only way out of that nightmare (either Churchill would have given up on "never surrender" or the British people would have elected pro-peace Oswald Mosley as Prime Minister), thus ending the Second World War with an isolationist America, a Latin America under American "protection", a British rump state (Britain will probably keep only its territories in the Americas plus Britain proper, with everything in Afro-Eurasia being ceded to the Axis Powers), and a world dominating Axis.
Once the Second World War is over, Germany and Japan will probably betray their allies and establish direct rule over any Axis nation that is still independent (such as Italy). Once that is done, Germany and Japan will settle into a Cold War-style arrangement after realizing that neither can dominate the other outright. Weapons of mass destruction will be developed (but probably not used, even the Nazis aren't crazy enough to agree to mutually assured destruction). America will continue dominating Latin America and staying out of the affairs of the Old World under the Democrats' New Deal Coalition, while Britain will either become a Nazi ally and potentially get swallowed by the Germans just like the rest of the minor nations in the Axis Powers (if Mosley becomes Prime Minister) OR Britain (under an anti-Nazi Conservative/Liberal/Labor government) will focus entirely on quietly rebuilding itself and take on a much more non-interventionist foreign policy (with their only foreign involvement being covert funding of rebels in Axis-occupied lands as well as working to establish a closer friendship with the United States in order to get the Americans to come out of their shells and help).
I personally think that the Nazis would collapse at some point in the 1960's or 1970's due to how unstable their economy was (a lot of it was command economics and those parts of it that were privately-run were so ultra-dependent on the war effort that I don't see how Nazi Germany could survive for more than a few decades once the wars are over). Japan was much more stable economically (with their initial problem being the obtainment of raw natural resources, which their victory in World War 2 would solve). I see Japan's economy as becoming more free market over time and causing a massive economic boom (like what happened with Francoist Spain IOTL), leading to much less reliance on war to maintain economic growth. In terms of social policy, the Imperial Rule Assistance Association would remain socially and politically authoritarian, ensuring that Japan maintains its traditional religious values as the market becomes freer and the economy starts booming (with this economic boom being juxtaposed as successful "Japanese capitalism" as opposed to the failures of Western consumerism).
Nazi Germany, on the other hand, would continue to cannibalize itself Stalin-style, with the extermination of the Jews being followed by the extermination of Slavs and Medes and everyone else who isn't Aryan. This nightmare ends when everyone gets disgusted at how Germany is slaughtering her own citizens by the millions and experiencing anemic growth because of it (and because of the aforementioned over-reliance on war to drive the economy). Following the death of the popular Hitler, one of his not-so-charismatic right hand men takes over (either Himmler or Goebbels or Goering) and tries to be even more hard-line Nazi in order to be admired like Hitler. This causes colonial rebellions to break out, with the SS (much like the IRL Stasi and Securitae) failing to stop the impoverished masses from overthrowing Nazism. Some of the breakaway states become Japanese "allies" (like most of the IRL former Warsaw Pact), other become British "allies" (like IRL Mongolia and North Korea to China), and some stay neutral (like IRL Moldova and Ukraine to Russia) or stay relatively pro-German (like IRL Belarus and Serbia to Russia).
Britain becomes like IRL People's Republic of China, adopting fascist economics while staying true to British traditions (just like IRL China adopted capitalist economics while staying true to Chinese traditions) and becoming an economic powerhouse by the time the Nazi empire collapses. America becomes like IRL India, with a massive population and massive natural resources but a struggling economy due to too much government intervention (all those social programs and jobs programs, while being great for short-term depression relief, are terrible for long-term standard economic policy) and due to the lack of a growing market (no mass immigration to America and no American economic imperialism, both due to the New Deal Coalition's continued isolationism, prevent the massive American post-war boom that we see IOTL). Germany, meanwhile, is taken over by the military. The Kaiser is restored to his position, but is subordinate to the military-appointed Chancellor (who is also known as the Generalissimo). Some of the Chancellors of the new Kaiserreich included famous military heros such as Erich von Manstein, Erwin Rommel, and Otto Skorzeny. Nazi ideologues are essentially purged from all positions of influence in Germany (much like the Communists in IRL Russia), with many Hitler-era politicians (such as Himmler, Goering, and Goebbels) being posthumously condemned and vilified. while many deceased Fascist leaders (such as Mussolini, Salazar, Horthy, and Franco) are rehabilitated and praised for their contributions to the "Reactionary Revolution".
Now, the new German military leadership look to reclaim their glorious empire (while freeing it of the old notions of Aryanism and command economics that, according to these officers, caused the fall of the Third Reich); leading them to pick fights with bordering minor nations that were former territories (like Russia's IRL wars with Georgia and Ukraine). Japan continues to expand, slowly but steadily, relishing its new role as the world's economic and military hegemon. Britain continues to build up its economy, becoming an economic rival to the Japanese as the British heavily industrialize their island and start flexing their muscles towards Ireland (just like China's ultra-industrialist economy and muscle flexing towards Taiwan). And the Americans, for the first time, began to look outward; hoping to take advantage of the worldwide chaos and re-energize the American economy with some foreign capital and traditional religious values (Imperial Japan style) as an ambitious group of fellows led by Ronald Reagan and George Bush (calling themselves the Neo-Conservatives, in that they are a new brand of American conservatism unlike that of the old isolationist Harding-Coolidge-Hoover Republicans) threaten to shake up the New Deal Coalition with their promises of a powerful and prosperous America (Reagan's "City on a Hill" speech is the perfect example of this).
