Since it’s a mythical match-up & so (unless specified otherwise) we can assume both men on their best night, it’s Sharkey on points for mine. I think very little of Shavers as a fighter, personally.
Sharkey wins if he doesn't get caught. If Shavers hits him with the right hand he clipped Holmes with, Sharkey is done for.
This is the sort of matchup where if they fought 10 times it'd be like 6-4 for Sharkey with a really diverse set of outcomes.