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
Calm path-routing logic puzzles that are pure constraint satisfaction.

Optimization · Pure Optimization
A classic point-and-click adventure that's a fixed set of logic puzzles to solve.
Lyne leans Optimization (Pure Optimization); Monkey Island 2 Special Edition: LeChuck's Revenge 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.
Lyne
Tracing paths has no time pressure
Monkey Island 2 Special Edition: LeChuck's Revenge
no reflex demand, point-and-click only
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Lyne
Pure solo logic - no opponent
Monkey Island 2 Special Edition: LeChuck's Revenge
no opposing agent to out-think
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Lyne
Every board is fully visible and deterministic
Monkey Island 2 Special Edition: LeChuck's Revenge
deterministic puzzle solutions
Monkey Island 2 Special Edition: LeChuck's Revenge leans a little harder on optimization, though the gap is small.
Lyne
Each board is a solvable path-routing constraint puzzle
Monkey Island 2 Special Edition: LeChuck's Revenge
inventory logic puzzles fully 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.