the goldberg-steamcrack supports multiplayer. https://gitlab.com/Mr_Goldberg/goldberg_emulator

I only tested it in lan, and it works great. Not sure if it works online, too. You may need hamachi.

And of course: online multiplayer with randos is probably not worth it, as others have pointed out. On one hands it’s probably a bitch to set up. On the other cheating is probably rampant.

have you tried cs.rin.ru?

have you tried cracking it yourself? (i.e. downloading it from steam, refunding it, and then applying some of the generic steam-cracks)