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

Execution · Light / Casual
A relaxed collect-everything playground with near-zero failure pressure.

Execution · Light / Casual
A breezy co-op brawler that tests little beyond button mashing with a friend.
LEGO Marvel's Avengers leans Execution (Light / Casual); Spider-Man: Friend or Foe leans Execution (Light / Casual).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
LEGO Marvel's Avengers
Mashing through enemies asks almost nothing of the hands
Spider-Man: Friend or Foe
Simple combo mashing clears nearly everything
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
LEGO Marvel's Avengers
No adaptive opposition anywhere in the sandbox
Spider-Man: Friend or Foe
Enemies attack on basic fixed scripts
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
LEGO Marvel's Avengers
Collectible locations are fixed, just initially unknown
Spider-Man: Friend or Foe
Levels and unlocks are fixed throughout
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
LEGO Marvel's Avengers
Hundred-percent completion is a checklist, not a puzzle
Spider-Man: Friend or Foe
Sidekick picks and upgrade tokens barely matter
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.