Check out ksmiz's thread for a cheat table with more options:
https://forums.nba-live.com/viewtopic.php?f=268&t=110651
Original post:
I got tired of waiting around for a tool for assigning cyberfaces, so I went ahead and figured out how to do it with Cheat Engine. I don't have much experience with Cheat Engine so I can't guarantee this will work for everyone (it might stop working once the game receives an update), but it worked for me, so I'll share it here and hopefully it will help someone.

Download:
http://www.mediafire.com/file/e1oagl1bjhvtbh1/file
Usage:
1) Attach Cheat Engine to the NBA 2K21 process
2) Load up the cheat table in Cheat Engine
3) Go to a player's Edit Player screen
4) Change CFID (and optionally First Name / Last Name) in the lower part of Cheat Engine
5) Exit Edit Player screen (save changes)