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
Isometric co-op puzzling testing coordination and trap-room solutions.

Optimization · Practiced Mastery
Mission-based sequel sending Luigi through five haunted mansions with the Poltergust.
Lara Croft and the Temple of Osiris leans Optimization (Practiced Mastery); Luigi's Mansion: Dark Moon 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.
Lara Croft and the Temple of Osiris
Twin-stick aiming and trap dodging take light skill
Luigi's Mansion: Dark Moon
Strobe timing and vacuum wrangling
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Lara Croft and the Temple of Osiris
Enemies swarm on fixed triggers
Luigi's Mansion: Dark Moon
Ghosts are scripted mischief, not adaptive
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Lara Croft and the Temple of Osiris
Puzzle and trap layouts are fixed once seen
Luigi's Mansion: Dark Moon
Mission layouts are fixed
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Lara Croft and the Temple of Osiris
Co-op puzzle solving and score routing lead the test
Luigi's Mansion: Dark Moon
Gem hunting and mission rank routing
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.