This mythical match-up has been done and done objectively at that. One of the main writers for Fight Saga (
www.fightsaga.com), Joe Herron (a huge Mayweather fan), got a well respected pro boxing trainer with three decades of experience, James Gogue, on the War a Week Radio Network to break it down stylistically, their skills and physical attributes. His analysis is easy enough to understand for a casual as well.
The video is nearly an hour long and analyzes Lomachenko at this point, after beating Nicholas Walters, vs "Pretty Boy" Floyd circa 2001 after he beat Diego Corrales. This was the version of Floyd at 130 pounds (where Lomachenko is now) with healthy hands and power, but, he wasn't in his prime quite yet and was still growing and developing his strength.
I'll say that everything that Gogue touches on is something I've already written about here and, in some cases, further elaborated on in this forum after studying Lomachenko on film. I've talked to this trainer/analyst many times. He's a knowledgeable guy that likes to talk to other analysts in boxing on Twitter (very respected analysts like Lee John Wylie). James Toney actually taught Gogue the Michigan Shell personally, and Toney was arguably the best at using it. Styles make fights though and this is just one trainer's opinion on the subject. He knows Floyd and his family personally.