Kingpin beat Red Skull hand to hand when he was in a cloned body of Cap.
To be fair though it wasn't long after he had been starved and imprisoned by Magneto, so you could say he didn't bring his A game.
I do think Kingpin would fair pretty well against Cap though. Would Iron Fist count seeing as he has, well the "Iron Fist"?
Shang Chi would be a good bet, even without using his Chi to amp, he should be able to take KingPin.
People forget that Kingpin is well trained in martial arts as well as sumo. Hes all muscle and his suit gives him extra protection(bullet proof usually).
Hes already beat the following in h2h already that i know of....
Spiderman, Daredevil, Captain America and Stalemated Batman(fight didnt continue after DD beat Scarecrow).
Thats a pretty impressive list imo.