Uhh what? I’ve been a supporter for multiplayer mods in D2R since it was announced lol. I was sad when they removed TCP/IP and was one of the first to ask here for its reimplementation, although that was obviously never going to happen in retrospect.
For the OP, as the others have said there’s no way to play mods with other people in D2R as they removed TCP/IP before launch and Open Bnet was never going to fly in a modern Bnet game. You’ll just have to wait for private servers, which there is one in the works but development is very slow and is probably a year out at least, probably multiple.