Power button is stuck

I know is an old question and most probably Jismy is no longer needed it.

The answer is: The process is a little complicated similar with changing battery process, but you have to take out also the main board, because the power and volume rocker buttons are on the same ribbon cable which is connected beneath the main board.

I replaced one year ago that ribbon cable.

As a starting point for the process you can use the battery replacement guide: Xiaomi Mi 10 Battery Replacement