Even in game the tribes often sent people out in groups to explore and hunt robots. It would be pretty easy to turn killing giant robots into an mmo. There’s enough gear in the games to make some basic archetypes prevalent in mmo games. There’s really just not an apparent healer, but you could work around that with a design where every player has to occasionally be the tank and then heal themselves when needed.

It wouldn’t be a fast paced “bullet time” style shooter like the main games, but there’s solid potential in it.