As we know, Germany was closely aligned with China in the 20s and 30s. What if they kept those ties up instead of taking Japan's side in the Sino-Japanese war?
It's somewhat outside the scope of DominusNovus' original post but I've sometimes wondered what might have been possible if Britain had tried to replace them after Germany's May 1938 recognition of Manchukuo, or possibly started building up links earlier due to Britain deciding to favour China in several situations in the 1930s such as their proposed currency reforms in 1934-35. Past history however could make that complicated.Further aggravating this is Germany lacked capitol for deep & influential investment. For that you were limited to New York & London.
IIRC from fairly early on after the Great War, or possibly even before then, I forget the dates, the British had already started withholding certain technical naval advances before the Alliance had ended. With Germany defeated, its fleet at the bottom of as Scapa Flow, and their economy constrained, Japan was one of the powers that were viewed as potential competitors/threats in the mid- to long-term future.Hmm. If one threw in an alternate history Britain maintaining the Anglo-Japanese Alliance too?
One of the complications here is China is more important economically than Japan over the long haul.