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 stealth-action game where planning routes past scripted guards is the deep skill.

Optimization · Practiced Mastery
A puzzle-leaning platformer testing perspective-flip problem solving more than reflexes.
Metal Gear Solid 2: Substance leans Optimization (Practiced Mastery); Super Paper Mario 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.
Metal Gear Solid 2: Substance
stealth timing and aim matter
Super Paper Mario
Light platforming demands, well below mainline Mario
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Metal Gear Solid 2: Substance
guards are scripted, no adaptation
Super Paper Mario
Enemies follow simple fixed patterns, no adaptation
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Metal Gear Solid 2: Substance
minor patrol randomness
Super Paper Mario
Dimension-flip secrets are scripted-but-unknown until found
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Metal Gear Solid 2: Substance
stealth routes and gadgets solvable
Super Paper Mario
Solving levels via the 2D/3D flip mechanic is the core test
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.