head to head
Neither is harder. They score identically on all four axes, so the difference between them is in kind, not degree.

Execution · Practiced Mastery
NES platformer that codified boss-weakness ordering and tight jump-and-shoot play.

Execution · Practiced Mastery
Memorising spawn patterns then executing them flawlessly under one-hit-death rules.
Mega Man 2 leans Execution (Practiced Mastery); Super Contra leans Execution (Practiced Mastery).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Mega Man 2
precise jumps and boss dodges under pressure
Super Contra
One-hit deaths demand precise dodging and constant accurate fire
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Mega Man 2
robot masters follow strict patterns
Super Contra
Alien waves follow fixed spawn scripts
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Mega Man 2
deterministic once stage layouts known
Super Contra
Nothing random once spawn patterns are memorised
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Mega Man 2
weapon-weakness ordering is the classic solve
Super Contra
Memorising spawns and weapon routes is half the run
A matching score does not mean a matching test. Two games can both sit at 10 on execution and demand completely different things of you - which is why the reasoning above matters more than the number beside it.