Well, I don't watch Gotham, so can't comment on Alfred. But the thing with Dexter is that he uses prep/surprise a lot. Normally, he has a syringe in his opponent's neck before they even know what's going on, so it's hard to gauge just how good his pure H2H is.
If this was the book version, I'd probably give it to him. The "dark passenger" is more like a supernatural force in the books (which actually seems to enhance him to some degree, with regards to stealth, senses etc.), as opposed to basically being just a label for Dex's dark subconscious, like in the show.
Alfred is able to take on guys that are 3x his size in pure H2H combat, who are also quite skilled.
For reference, a guy who was giving James Gordon trouble without even coming close to going all-out, was only just fighting on par with Alfred. (Who I honestly thought was winning the fight, till he got thrown out a ****ing window.)
Originally posted by TheLordofMurderAlfred has better showings, in all honesty, and they only stalemated, IIRC.
Dexter wins...Near the end of season 1, he was able to physically out fight Sargeant James Dokes who was extremely powerful physically and had extensive military training as special ops...
Inaddition, Dexter is much younger than Alfred and in better athletic condition...