Started looking into current 1.21.0 mod list compatibility to see what we're still waiting on.
Results: https://pastebin.com/bcxHCTYA
>why is the formatting so fucking weird?
Pastebin a shit.

As for cracked clients, the archive.org client is not cracked, will have to wait for a cracked ver to turn up.
Probably a while to wait before we go to 1.21.0.