US isolationists had prevented lend/lease and there was no Pearl Harbour

For the Japanese to keep America at bey they need to overcome the US embargo, this could be done this way.

Sometime in 1940 or 1941 come to a peace arrangement with Nationalist China, Japan could still save face by pulling back her troops to within a sphere of influence in Northern China and lease Chinese Ports, Japan does not need to say sorry but to offer a understanding of regret for her actions and also within this Japan and Nationalist China could form a new partnership that confronts the Chinese Communists, this still means that Japan still plays a role militarily within China but as an ally of Nationalist China.

The US having gained a peace treaty of sort in between the Japanese and Nationalist Chinese lifts it's embargo on Japan thus no need to for Japan to launch any reprisal raids against America thus keeping America out of the war, also one other main factor once the US embargo is lifted Japan drops her goal at creating a South East Asia Co-Prosperity Region.

v.R

 

Yes, I share this viewpoint too. There were indications that the Japanese were getting weary with the war in China so it's entirely within the realm of possibility that the more reasonable Japanese factions could take the upper hand. However, if I remember correctly these factions did make the attempt and failed.
As for the situation in Europe, if the proposed what if actually happened, I don't see the British losing the war. I think the worst that could've happened would be that Britain would've opted for a negotiated peace, which was what Hitler actually wanted. As for the Russian front, I don't see Germany defeating the Soviet Union. It would've degenerated into a a long dragged out fight, possibly turning into something similar to the situation of World War I.
With Britain opting for peace, it frees Germany to get the needed resources to sustain its forces in the field. However, the Soviet Union is larger and more able to take what Germany can dish out, so it's likelier that both sides would end up exhausted, and the fighting would generally be skirmishes that would go on for several years until either Hitler or Stalin is removed from the picture. They both have huge egos and neither of them would be willing admit they can't succeed. Removing either one of these dictatorships is the only way I think a war between Germany and the USSR could be ended.