Well, allies need ground troops to occupy Germany, but what about the shitload of planes that were used to bomb it into submission? And what about the USSR, if I remember my history books correctly, once Germany fell, it shifted it's attention to China and pretty much blited through it.
Soviets
most likely enter the war September 45 or max a few months after that.
The 8th and 9th Air Forces also stayed in Europe for a good while, as did the main body of the RAF. Also like all war products, aircraft were made for wartime use and just shipping or flying them halfway around the world to the Pacific would not have been very practical... Ie. RR Merlin-Packards in P-51s only had service life of less than 60 hours. Shipping them to the Pacific would have taken months, and as most planes were not designed to be disassembled and crated, would have taken lots of labour and time, just to get the thousands of already planes with already stressed airframes and lots of hours in their engines, and no intake air sand filters.
Like one of the advantages of the Bf 109 was in that it was by design made for field use: 100 hour engine life for DB601 and 605, V-inline engine inverted for much easier maintenance(cylinder heads down, no need to use ladders, everything checkable by just raising one cowling), detachable wings and frame partially field-repairable. Spitfires might have had fancy looking elliptic wings, but they'd build 3 equally effective 109s at the cost of a single spit, and those 109s didnt have to be sent back to the factory when they needed a new wing or tail.
Theres lots of British and US naval units from Europe, though. Such as good part of the Royal Navy's battleship and carrier fleet that was mainly just killing time, at anchor in Scapa Flow...