Question

who is the most powerful Avenger in MCU

Answer 1

Hulk may be the strongest Avenger, but there's no doubt Thor is the mightiest. Not only is he a god — and a god worthy of one of the most powerful weapons in the universe at that — he's been an integral part of the Avengers since founding it in 1963, despite having to protect all the nine realms

Answer 2

Here is your answer....

I think that of all the Avengers these are the strongest: Thor, Hulk, and maybe Steve.

Hope it helps you.