https://wccftech.com/new-halo-reach-pc-character-mod/

A new Halo Reach PC character mod has been released which unlocks all player customizations in the recently released PC version of Halo Reach.

Created by modder ‘0sedax’, this modification only works if Halo Reach is launched with EAC (Easy Anti-Cheat) disabled. As covered earlier, Halo Reach on PC includes an anticheat bypass option to allow modders to experiment and tweak the shooter. "We’re still working to improve this down the road, but for now you will have an option when you launch to bypass antichea", developer 343 Industries wrote on the Halo Reddit. "This will allow you to play around with campaign and customs but not allow you to play any match made games. I highly suggest making a copy/backup of anything you modify so you’ll be able to switch back and forth easily."