Spider-man vs Killmonger:
Killmonger should take it, especially if we go with the Spidey suit from this picture ( ie, not the ever ambiguous Iron Spider armor ). Killmonger is in the same physical weight class as Peter, is much more skilled, and his own suit provides both protection and claws. There just isn't much Peter can do to turn this tide, since he can't stay at range indefinitely, isn't going to do much damage even while he is at range, and ultimately doesn't want to be in close, because Killmonger will hurt him much more than the reverse. Yes, webbing, but with Killmonger having both strength and claws, webbing won't do more than temporarily impede him, and I'm fairly certain Peter will run out of webbing before Killmonger will run out of "cut and break his way free of webbing".
The vibranium body suits are just a *really* tough nut to crack. They kind of bump whoever wears them up one "weight class", with an equivalent opponent needing at *least* a weapon capable of punching them to be competitive.