Then I try to follow your timeline.
Although Japanese Navy fought better than real history,and might sunk all the CV of US navy,they could not defeat USA.
Feb 1942,Japanese Navy attempted to land on America,but failed.Although they had controled the whole Pacific,the Zero fighters carried by their CVs were not enough for a massive dogfight against all the fighters of USA,and the soldiers they could land were not enough,either.The tank and artillery of Japanese army were also laughable at that time.
San Francisco and Los angeles were almost ruined in the war,but the productivity of USA was not reduced much.
Mar 1942,Hitler claimed that it's impossible to help Japan,as he did not have enough ships to cross the Atlantic.What's more,USSR was becoming stronger and stronger,and he had to keep his army in Europe,as Stalin might change his mind at any time.He also need to control all the lands he got from UK,including Africa and Middle east.At last,after a cruel war,Germany needed peace to hold all the land they obtained in the war firmly,and actualize all the promises he made to everyone before the war.
In fact,I suppose that Hitler could realize that Japan would finally lose the war against USA because of low productivity.And he really need peace to change all the potential of the newly occupied lands into real military strength,even into the living standard of German people,as he promised before the war.
Apr 1942,Stalin decided to provide fighters,bombers,tanks and all other equipments for Mao,as he found out that although USA could finally win the war against Japan,they could do nothing from 1942 to 1944,and he would produce too much weapon in 1943 and 1944 without the war against Nazi.Now he could hold the west line firmly,and although he could not declare a war against Japan because of Hitler's attitude,through helping Mao,he could achieve same goal even earlier.
May 1942,USSR declared war on UK to obtain India,as UK had lost almost all the military strength in the war against Nazi,and if USSR standed still,Japan would got India.Although Japanese was really angry,they could do nothing as they were afraid of USSR's military strength.USA also kept silent,as they knew that they would have nothing to gain if they launch a war against USSR under such condition,but Chiang Kai-shek declared war against USSR and Mao at once,as the war would cut off the last channel for him to get weapon and supply from USA and UK,and Mao would grow out of control with weapon supply from USSR.Of course,Chiang Kai-shek knew that USSR would defeat him easily,but he had no choice.
June 1942,Japan made peace with Chiang Kai-shek,as both sides were in danger because of Stalin's decision.At the same time,Mao had equiped all his army with newest weapons from USSR.
Aug 1942,Japan finally conquered whole Australia,New Zealand,and all the southeast Asia.
At same time,USSR successfully conquered India,all the UK army retreated to China and joined Chiang's side.
Chiang's army surrounded Yan'an,attempted to defeat Mao before the arrival of reinforcement from USSR.
Sep 1942,reinforcement from USSR arrived on time,and Chiang suffered a great defeat.
Japan asked Nazi if they could declare war on USSR together,but Hitler rejected,as although Stalin sent part of his troops to India and China,he left even more troops in Europe than one year ago,and they were more prepared,but Hitler's troops were still scattered here and there,as he got too much land in a short time,and UK was not defeated completely,either.
Oct 1942,Japan asked USSR to divide China with a pact,but Stalin rejected at once,and Mao told everyone that he would not sign any pact until all the invaders were drove out of China.
Nov 1942,Chiang had to retreat to Sichuan to maintain the last line of defence with the help of mountainous area,where USSR's tanks could not pass.
Mao launched several battles against Japanese,and obtained great success with the help of advanced weapons and local peasants.Japanese army's weakness exposed completely in these battles.In fact,compared with USSR weapons,Japanese weapons were completely out of date.
USA Navy could get back their advantage in early 1944,even they lost all their carriers in 1941.But according to my plan,USSR might be able to defeat Japan before that.And Hitler's best choice was to keep silent and let Japan to be defeated.