Your challenge, if you like it, is to have at least an Essex or Yorktown class carrier serve in Europe during WW2, preferably with a pod after 31 December 1942 for the Essex and 11 December 1941 for the Yorktown and better with two or more carriers if it doesn't impact Pacific operations. Conditions should be such that the carrier stay in Europe until 1945 if not sunk [and the carrier transferred to make up for British losses should be better than the German aircraft carrier or better Italian, U boat and Luftwaffe performance].
The pods don't matter though, because they may have bigger impacts on history. However, the circumstances that lead to the Essex[es] serving in Europe need to be possible and WW2 events following the pod should lead to total Allied victory over both Germany and Japan in 1945 as well.
[Preferably the otl surrender dates for both Germany and Japan should still be accomplished by the pod.] The actual timeframe can be extended to 1946 if you wish, due to impacts for the Pacific and events in Europe.
The pods don't matter though, because they may have bigger impacts on history. However, the circumstances that lead to the Essex[es] serving in Europe need to be possible and WW2 events following the pod should lead to total Allied victory over both Germany and Japan in 1945 as well.
[Preferably the otl surrender dates for both Germany and Japan should still be accomplished by the pod.] The actual timeframe can be extended to 1946 if you wish, due to impacts for the Pacific and events in Europe.