head to head
Neither is harder. They score identically on all four axes, so the difference between them is in kind, not degree.

Optimization · Pure Optimization
Board-game distillation of Hitman into elegant fully-solvable turn puzzles.

Optimization · Pure Optimization
A cerebral puzzle-adventure that is essentially a logic puzzle to be fully solved.
Hitman Go leans Optimization (Pure Optimization); Riven: The Sequel to Myst 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.
Hitman Go
Turn-based taps, zero dexterity
Riven: The Sequel to Myst
no reflex or physical skill required
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Hitman Go
Enemy pieces move on fixed deterministic rules
Riven: The Sequel to Myst
no opponent present in the game
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Hitman Go
All information visible on the board
Riven: The Sequel to Myst
fully deterministic puzzle world
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Hitman Go
Each diorama is a literally solvable movement puzzle
Riven: The Sequel to Myst
pure logic-puzzle solving, walkthrough-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.