Suggested by Destroyer Jin is a pretty strong hand to hand fighter and he even has a demon mode as well. This makes him an extra dangerous fighter for sure. That being said, Killua already had a good degree of super strength and speed ever since he was a little kid. His abilities have only grown since then and I don’t even think it would be much of a fight at this point. Jin has the right amount of destructive power, but he won’t be able to hit Killua. Killua wins.