Chael is the first name that pops into mind. I think he'd do pretty well in the WWE if given a proper chance. That's always the risk people take in the WWE though, you could be the best talent in the world but if you don't get a proper shake you're not going anywhere. They have their guys they want to push forward and if you're not one of them, you're going to be lucky to get anything. Chael has the bonus of being well known already so he'd probably at least get a decent chance but it'd be an uphill battle even for him.
Outside of Chael, Barnett could do well, maybe Conor. The thing Barnett and Chael have going for them is they at least have some grappling experience they can fall back to in order to "fill time" in a match. Takedowns and rest holds would be easy for them to fit in. Conor has a striking base which would actually kinda hurt him since it'd be harder to switch off the instinct to hit the guys you're going up against.
I don't think Ronda would do well though. Her Judo would make for some flashy moves in matches but not enough to carry her through, and her acting skills aren't great as it is so given a script to memorize and recite in front of a live audience would probably end poorly. She'd be good for a gimmick match or two, but she wouldn't go far.