Anyone from the MCU could take out Batman, even Ant-Man. Hell, Rocket Raccoon would give him space fleas or, you know, shoot him in the face.
First off: Love Ant-Man. Second: One errant strike to his magical belt buckle, and that dude is banished to the microverse. Scott Lang is rad, but a well-times can of Raid takes care of that fight, and that's before we talk about the expanding polymers and EMP shit he carries.
See, I read Marvel AND DC comics, and it never ceases to amuse me how chauvinistic each company's respective fans are about who would win in a fight.
As for Rocket, I'd love to see him paired off with Dex-Starr.