baritone not walking by itself

You'd need a mod which, for the server, is indistinguishable from immersive portals. I.e. it must have the same id and version (easy), register the same blocks / items (still pretty easy) and handle the same network packets. I don't think that's a feasible workaround and is probably more effort than porting #2430 to whatever version you need.

remove immersive portals

remove immersive portals

is there a way for the server to think that the mod is there because now it says this

probably not