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
A gentle platformer where copying enemy abilities and light timing carries progress.

Execution · Practiced Mastery
A family-tuned brawler-platformer testing modest timing and simple puzzle solutions.
Kirby: Nightmare in Dream Land leans Execution (Practiced Mastery); Knack II 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.
Kirby: Nightmare in Dream Land
light platforming and timing precision
Knack II
Light combo timing and platforming pitched at families
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Kirby: Nightmare in Dream Land
scripted enemies, no adaptation
Knack II
Enemies run simple scripts without adaptation
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Kirby: Nightmare in Dream Land
minimal randomness
Knack II
Levels are fixed with nothing hidden beyond first sight
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Kirby: Nightmare in Dream Land
ability combos lightly solvable
Knack II
Size-swap puzzles have single obvious solutions
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.