You got basically ****.. Because Robinson was in his prime at welter dumb****. I win you lose. Game over. Keep talking alone like a ****** nerd mad lmao.
Given that the Suga Man is bigger, hits much harder and his offensive arsenal was amazing, he'll likely KO Mayweather or win decisively on points. I'm not completely counting out a Floyd win by running and outpointing SRR, but the chances for that are very slim. If the Suga Man sees that he's behind on points and likely to loose, he'll disregard caution and go all out on Floyd, and most likely KO him. Given that he can withstand Floyd's punches, this is a very likely scenario.
I think their speed is close if we look at 05-07 FMJ. But more importantly Robinson is much much easier to hit than Mayweather AND Mayweather's punches are straighter. Wider punches are easier to evade. For those reasons I see Mayweather beating Robinson to the punch and outboxing him. You initially laughed at this. But what I'd advice doing is watching both Robinson-Turpin fights. Turpin is outboxing Robinson in both fights, with very similar height/reach to Mayweather. The strength and weight factor still comes into the boxing too. Nearly of Mayweathers welter opposition were bigger weighing 155-165lbs rehydated on fight night. In Robinsons day they would be middleweights. The only opponents who weighed 147 or under were Mitchell, Judah, Marquez and Pacquaio. Even Hatton was 155+ against Mayweather. In all these fights you can see Mayweathers punches had more effect, he wasn't pressured on the backfoot barring the Pacquaio fight and those men weren't able to manhandle him. Mayweather at 147 can hold ring centre, push Robinson back in clinches and hurt Robinson at this weight class. I do see an argument for Robinson knocking Mayweather out. But not outboxing him