You can't be banned for using en passant. Even if you get reported, you won't be banned/muted. En passant is a legal move, as castling. So en passant whenever you can if you want, don't care about the insults if you en passant, block them, report for verbel abuse and ignore.
enpassant move illegal????

Congrats on being in Legend League ! Oh btw alt account are not allowed, just saying
Actually, since recently, it is actually allowed, but of course there are some restrictions.
https://support.chess.com/article/596-can-i-have-multiple-accounts

Technically en passant is not illegal, but there is ALWAYS going ot be those who think it's suspicious.

Congrats on being in Legend League ! Oh btw alt account are not allowed, just saying
Actually, since recently, it is actually allowed, but of course there are some restrictions.
https://support.chess.com/article/596-can-i-have-multiple-accounts
This person is playing games against alts and winning every game. Every game is 2-3 moves. Bannable ?
I’ve been playing chess for half a year now and as a teenager who has aquired the legend rank, i’m asking if the enpassant move is considered cheating. Out of over 1000+ games, I’ve only seen one person use it and I have been called a cheater and reported for using that move. I’m just wondering if I will get banned for using the enpassant move.
Innovative flex. Still weird.

Congrats on being in Legend League ! Oh btw alt account are not allowed, just saying
Actually, since recently, it is actually allowed, but of course there are some restrictions.
https://support.chess.com/article/596-can-i-have-multiple-accounts
This person is playing games against alts and winning every game. Every game is 2-3 moves. Bannable ?
That is another matter completely. I haven't looked at his account at all. I was answering the post that said that having alts is not allowed, which is not true since recently. The example you've mentioned is obviously one of the things that are not allowed.
Nope it’s allowed