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

Optimization · Practiced Mastery
A 3DS Kirby playing with foreground-background depth and the vacuum-everything Hypernova power.

Optimization · Practiced Mastery
A relaxed collect-athon testing character-ability matching far more than any skill ceiling.
Kirby: Triple Deluxe leans Optimization (Practiced Mastery); LEGO Batman 2: DC Super Heroes leans Optimization (Practiced Mastery).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Kirby: Triple Deluxe
Easy main game, modest arena challenges
LEGO Batman 2: DC Super Heroes
Button-mashing combat designed for children's hands
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Kirby: Triple Deluxe
Bosses follow fixed patterns
LEGO Batman 2: DC Super Heroes
Enemies are harmless scripted waves
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Kirby: Triple Deluxe
Levels fully deterministic
LEGO Batman 2: DC Super Heroes
Stud and minikit locations are fixed once known
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Kirby: Triple Deluxe
Sun-stone hunting and foreground-background gimmick puzzles
LEGO Batman 2: DC Super Heroes
Matching character abilities to gated collectibles
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.