Hamed has the power that no Mayweather opponent ever possessed and an unorthodox style that Mayweather would never have encountered before. Hamed by TKO.
Young Floyd was calling Hamed out back when He was at 130... not 100%, but He might've been even talking about dropping down to 126 for that. Either way, easy one for Floyd and total nightmare for Hamed - unless cutting extra 2 or 4 pounds could've drained Floyd.
Mayweather has the defensive skills and footwork to nullify much of what Hamed would try to do. He also has the speed and offensive capabilities to capitalize on the many mistakes Hamed is likely to make. Hamed could sneak a bomb in, but after Mayweather takes inventory and adjusts - I think Hamed has little hope of being productive. I don't think Mayweather stops him, but he's likely to catch him off balance and get a knockdown or two and earn a wide UD in my opinion.
Floyd would tag Hamed every time Prince tried to open up. This is the worst possible matchup for Naseem, even worse than Barrera, where I felt he had some decent moments was just outfought and unprepared mentally. I don't think Hamed catches Floyd with anything crazy, and even if he did, I think Floyd would take it just fine. Floyd would have it his way, all day, and probably only lose 2-3 rounds max. I don't see where Hamed would do something to alter Floyd's gameplan or even startle him.