This depends a lot on motivation. Bloodlusted, it's a stomp for Vision in all rounds. We see him phase his arm into bots in AoU, so he could just do that to anybody, but he doesn't. So morals off, he just wins.

Morals on, I can't really figure how he would win, but I also don't think he can lose? His offensive abilities are shooting beams and hitting stuff. In the airport fight in Civil War, he basically does nothing. He shoots some beams and cannon balls into Ant-Man, and that's basically it. But he has a sort of implied invulnerability to everyone except Wanda and Hawkeye, and Hawkeye was only able to disable him for a minute. Thor and Hulk lack either of those abilities, so I don't think they can really injure Vision, either.

Round 1: Can't really know this, but I'd guess Thunder God Thor's lightning can probably match Vision's beams, so that's a stalemate. If Vision starts phasing, Thor's done, but he doesn't seem to do that, so they just punch each other until they either get bored or Vision decides to kill Thor, which is unlikely.

Round 2: Same thing, except Hulk won't get bored, so they'll just fight until Vision decides to end it.

Not much of a fight, imo.