CM Punk trains jiu jitsu but throws a white belt on when he trains with the gracie's so I have no Idea how good he is.
Little known fact about Daniel Bryan is that he used to live with Lyoto Machida in Japan. This doesn't make him a good fighter but is pretty funny.
Ziggler and Swagger both have great amateur wrestling records and you look at how well askren has done you imagine that they could both hold their own in Bellator at least.
Taker expressed that if mma was as hot as it is now he would have done that instead of wrestling. Whether this means he would be good or not is up for question.
Remember Daniel Puder? Well he was undefeated and Benoit and Guerrero used to beat the shit out him. Guys with their commitment would probably do a decent job.
As for the op's suggestion of Henry and Cena you must be trolling and probably are. Both of these would be terrible Cena can't even make a fake punch look good and henry is painfully slow.
Another interesting question is who could cross over the other way. There isn't too much precedence of this with Shamrock and Severn crossing over to little critical success. I'm sure Chael would be able to do it with ease and I hope Vince Mcmahon is aware of his existence.
As someone suggested previously Josh Barnett is one who has had a great deal of success in both.
Harry Smith (David Hart Smith) left wwe last year and intended to go into mma. Be interesting to see if the Hart dungeon training crosses over to mma at all. I know that they used to learn legit holds and seems like a traditional catch wrestling type of camp.
The great Regal is certainly a throwback to the old catch wresltling style where they used to go round challenging locals. He admits himself that he wasn't gifted athletically so he may not have done too well.
Oh and the Del Rio cro cop fight looked as fake as giant silva vs akebono. I think Ricardo Rodriguez could last longer than Del Rio did.