Clinton would win Pennsylvania, Trump still would win WI and MI and Manchin would get obliterated in 2018.
I'd flip Michigan and Pennsylvania the other way but about this. Manchin doesn't do much of a effect and i doubt Clinton would be anywhere near close in West Virginia if he was on the ticket. The most obvious effect of this would be the fact that Manchin would lose big time in 2018. He would be seen as a traitor to many of Trump voters in the state who would vote republican to replace him. Also his connection with Clinton on the same ticket with her would tarnish his image.