It work in singleplayer but not in multiplayer, i am playing in a realms server in 1.20.1.
If you need extra info, tell me
Good luck !

Sorting is done server side to avoid ghost items. If you want to be able to sort while you’re on a server, the server will need to be running the mod

That's sad.

ikr

Yeah, this is a client and server side mod. There are other mods that work only on the client. I'd refer you to them if you want client only functionality.