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

Optimization · Practiced Mastery
Greek-flavored action RPG where build-crafting drives long-haul play.

Execution · Practiced Mastery
Open-world western about an outlaw forced to hunt down his old gang.
Assassin's Creed Odyssey leans Optimization (Practiced Mastery); Red Dead Redemption leans Execution (Practiced Mastery).
Red Dead Redemption leans a little harder on execution, though the gap is small.
Assassin's Creed Odyssey
Parry and dodge timing required, not punishing.
Red Dead Redemption
Dead Eye softens but gunplay still wants aim
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Assassin's Creed Odyssey
Mercenary AI scripted, not adaptive.
Red Dead Redemption
Multiplayer skirmishes add light human prediction
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Assassin's Creed Odyssey
Loot tiers and mercenary spawns randomized.
Red Dead Redemption
Ambient events and spawns vary mildly
Assassin's Creed Odyssey leans a little harder on optimization, though the gap is small.
Assassin's Creed Odyssey
Engravings, gear sets, builds deeply solvable.
Red Dead Redemption
Mission approaches and economy are learnable
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.