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
The 1981 arcade classic of climbing girders and dodging barrels.

Execution · Practiced Mastery
Zero awakens to lead a resistance in a harsh, rank-graded GBA action series debut.
Donkey Kong leans Execution (Practiced Mastery); Mega Man Zero 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.
Donkey Kong
Frame-tight jumps over barrels under arcade pressure
Mega Man Zero
Punishing GBA action with strict ranking on damage
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Donkey Kong
Fixed arcade patterns, nothing adapts
Mega Man Zero
All bosses are pattern-based
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Donkey Kong
Barrel bounces add slight unpredictability
Mega Man Zero
Cyber-elf locations hidden at first
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Donkey Kong
Stage patterns and score routes fully learnable
Mega Man Zero
Rank system penalises elf use, rewarding optimised clean runs
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.