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

Optimization · Pure Optimization
Hoenn's definitive version, crowned by the strategy-heavy Battle Frontier.

Optimization · Pure Optimization
The Myst sequel: a slow, wordless puzzle adventure solved by observing an alien world's internal logic.
Pokémon Emerald leans Optimization (Pure Optimization); Riven leans Optimization (Pure Optimization).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Pokémon Emerald
Turn-based commands only
Riven
Point-and-click; no dexterity required at all
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Pokémon Emerald
Battle Frontier AI is fixed-policy
Riven
No opponent of any kind
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Pokémon Emerald
Encounter RNG and Frontier hax
Riven
Information is hidden only until you observe it
Riven leans a little harder on optimization, though the gap is small.
Pokémon Emerald
EVs, movesets, and Frontier strategy run deep
Riven
Deciphering the world's logic is one giant solvable puzzle
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.