Batman (in Silver Surfer's body) vs. Doctor Doom (in Superman's body)

Neither has time to prepare, they're instant placed in the respective bodies and must figure the abilities out as they go.

I say Batman because Doom will still have the K-nite weakness and Batman will know about it from first hand exprience and use it against Doom.

They look mentally retarded and walk up to each other drooling and throw girl punches but if they can work the bodys right I would say Batman he is a dectective and can figure how to beat someone in Supes body

Doom.

He has the ability to mind swap himself. He's one step away from having Surfer's powers again.

Batman, he'll just absorb the yellow sun radiation out of doom's body.

I'm with Doom because doing something you already know, mindswapping, is much easier than trying to operate powers you've never seen before and know nothing about.

Bat-Surfer wins. Cosmic awareness owns all.