head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is variance, and it is a single point.

Optimization · Light / Casual
Short narrative horror about a doomed freighter crew told in fractured time.

Variance · Light / Casual
A painterly hidden-object game testing visual scanning patience.
Mouthwashing leans Optimization (Light / Casual); Under Leaves leans Variance (Light / Casual).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Mouthwashing
Walking and simple interactions
Under Leaves
Tapping spotted objects requires nothing physical
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Mouthwashing
No opposition; it is a story
Under Leaves
No opponent exists
Under Leaves leans a little harder on variance, though the gap is small.
Mouthwashing
Narrative surprises only on first viewing
Under Leaves
Object locations are hidden until found - that is the game
Mouthwashing leans a little harder on optimization, though the gap is small.
Mouthwashing
Light puzzles guide a fixed story
Under Leaves
Systematic scanning is the only technique
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.