If Mayweather came out of retirement and signed to fight Loma in 2019. Who would you pick to win?

Floyd.

He's tougher/more clever in the ring than many like to admit. I've watched that clown dig down many times over the years (mainly in the first half of his pro career with some in the beginning of the second half, finishing with have to dig down with Maidana).
Of course the formidable Loma would still be prime or close to it, but my gut leans to Floyd mainly due to size, and lack of seeing how Loma reacts when pushed these days.
I just think Floyd will be able to adjust to handle what would be a barrage from Loma I dunno.

 

Yeah, agreed.