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.

Variance · Light / Casual
A live-action FMV thriller steered through touchpad choices and gestures.

Optimization · Light / Casual
A branching visual novel that tests little beyond exploring choice routes.
Erica leans Variance (Light / Casual); Everlasting Summer leans Optimization (Light / Casual).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Erica
Touch gestures with no skill ceiling
Everlasting Summer
Reading and clicking choices, nothing physical
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Erica
No opponent
Everlasting Summer
No opponent - characters follow fixed branching scripts
Erica leans a little harder on variance, though the gap is small.
Erica
Branch outcomes hidden on first viewing
Everlasting Summer
Route outcomes are hidden only until first playthroughs
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Erica
Mapping choice branches across replays
Everlasting Summer
Mapping choice branches to endings is trivially solvable
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.