How do you grapple someone like Sarychev?
I legit don't know if I, a 225lbs male, can effectively armlock him, considering he benched 320kg - thrice my weight - raw, and deadlifted I think 400kg.

This isn't a "can a wrestler kill he", this is a "what can work on him and what can't". I'm legit curious how his strength, muscle and fat change the mechanics of grappling. I mean I doubt you can even throw him on pavement and get results unless he lands on his neck because he is cushioned by fat & muscle.