The Spanish American War and the Boxer Rebellion both happened right before 1900, otherwise Germany could have picked up more Chinese territories or the Philippines with some changes to the events.
However there are some post-1900 elements you can use. The main one is Japan gets crushed like a bug by Tsarist Russia, which is implausible but would at least have some serious butterflies. If Japan becomes a weak state, it can no longer do much in China, leaving China wide open for German influence. And you can do alot with China in the post-1912 chaos. If Tsarist Russia reveals itself as a military superpower, the power dynamics in Europe will probably change completely. You should see Britain siding with Germany against Russia and France for balance of power reasons. That butteflies away World War I.
So OK, with generating lots of butterflies from reversing the Russo-Japanese War, you get a fascist or quasi fascist USA, because the no or different World War I changes the Depression, facing off against Hohenzollern Germany and Britain, and the Germans have a powerful ally with China or are heavily involved in China. Since Britain is an ally, the Germans don't have to concentrate everything in the North Sea, and build up their Far Eastern fleet and equip it with carriers. The movement of the US Pacific Fleet from San Diego to Hawaii still happens somehow. The world war is between Britain/ Germany and allies against the USA as allies, and the Europeans strike first with a British strike against Norfolk and a German strike against Pearl Harbor using carrier aircraft. There, I think I did it.