as Fighters I respect both these guys (who wouldn't?) and am not on one side or the other. but I reckon Floyd will win on Points. you can't really say UD because look what happened on the scorecards v Canelo!
I think Floyd will avoid Manny's attacks , clinching where necessary, but connect enough on the counter to win rounds. it will be close for the first half of the fight and Floyd will gradually pull away and realistically win by 3-4 rounds.
Floyd may end up looking like a "mini Andre Ward", and it won't be pretty or a great fight as such. Pretty standard Floyd fight really.