It's possible that the Japanese changes its diplomacy enough to not kick in the various embargoes. If they don't sign the Tripartite Pact and keep their distance from the Nazis, and make it well known they will honor their non-aggression pact with the Soviet Union even after June 22, 1941, then the US might never slap the embargo on Japan. It's unlikely, but still possible, enough to comment on the POD. Japan can still continue its futile war against China and not need to worry about where it'll gets its oil or scrap iron.
In which case, the US likely still ramps up some aide to China. It may not send white volunteers to fly in planes, but they could arrange a flying school for Chinese-American volunteers or travelling Chinese pilots in the states and provide China some form of Lend Lease, enough to get the Japanese upset, but not start a war.
So in 1942 we will see aide flow uninterrupted on the Burma Road and eventually a Burma-Yunnan railroad. Aid and material will flow into China that will eventually help the Nationalist army. But the Nationalists are a long, long way from mounting any kind of successful offensive. Maybe by 1945/1946 the Nationalists could consider some limited offensive. They still have major issues with command & control, logistics, and more. So we have continued stalemate in China for at least 5 years or so.
So what happens in Europe? A lot depends on whether you think the US still gets involved in the war or not. Let's assume for now that it does not.
Without the problems in the Far East, Britain is in far better position. Rather than experience initial problems in 1942 and not beat back Rommel until late 1942, they can probably clear out North Africa by mid 1942 and invade Sicily by late 1942. Britain won't be attempting any kind of cross channel invasion and will prefer diversionary actions in the Mediterranean. The war on the Eastern Front will play out as normal. After Stalingrad, it's obvious that Germany cannot win, although it's possible a stalemate may still happen.
Most of Hitler's allies will now be wanting to get out of the war, but they won't want to risk Hitler's wrath. Britain will probably prepare for operations against Italy to knock her out of the war. Can Britain do so better on her own (since she won't need to accommodate the US on any cross channel invasion), or will we get the same hard slog because the Germans occupy Italy too quickly?
In any case, I see a British strategy to fight in the Balkans and lock up with the Soviets there. If so, eventually we get a British occupied Italy and Greece, and Bulgaria defects to the Allied camp. Romania and Hungary are overrun by the Red Army. Yugoslavia probably split between them and the Partisans. By end of 1944, the British are posed to enter Austria and then into Bavaria. Soviets are in Poland and Hungary. There is very heavy fighting since the Germans don't need to station much troops in the West.
I'm not exactly sure how 1945 will turn out except that Germany is eventually defeated. The British can probably arrange for Western Europe to be free of the Soviets, but most of Eastern Europe is still screwed. The Soviets will have a much larger occupation zone in Germany. If the British come up through the south, then they'll have Bavaria and do everythng to keep the Soviets from having access to the North Sea. Everything else is negotiable. Soviets probably take Hesse and some of Lower Saxony. The Vichy government might still be in power although it will "pardon" any Free French and need to reconcile Petainists and DeGaullists.
In any case, the war in Europe will be over by mid 1946 at the latest. At which point Britain and Soviet Union will likely begin applying pressure to Japan to make peace with China just as China is beginning to have a real centralized army again.
Europe thought is in a lot of trouble. Britain alone can't do a Marshall Plan. And if the US never joined the war, will the US do anything substantial to help out Europe?