I'd say 230lbs. He is still going to be quick handed and powerful but would be able to move much faster.
His best performance (not to mention health) would be lower, maybe even CW, but since he wants to fight current HWs probably around there.
He could never be anything other than a HW, he's not "tiny", however looking at his frame and rotundness, I'd say he should be no larger than 220ish.
About 220. Don’t buy into the nonsense that he performs better at higher weights. That to me just translates to him being lethargic whilst cutting.
220 or thereabouts. He's quite wide in the shoulders and likely quite stocky, like a slightly larger Oscar Bonavena.