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

Execution · Practiced Mastery
Foundational ice hockey sim testing stick timing and exploiting goalie angles.

Execution · Pure Mechanics
Motion-controlled tennis, bowling, golf, baseball and boxing built around simple swing gestures.
NHL Hockey leans Execution (Practiced Mastery); Wii Sports leans Execution (Pure Mechanics).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
NHL Hockey
Skating angles, pass timing and shot placement decide goals
Wii Sports
Motion swing timing and accuracy decide every event
NHL Hockey leans a little harder on reads, though the gap is small.
NHL Hockey
Against a human, baiting checks and goalie reads matter
Wii Sports
Casual local opponents add light mind games
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
NHL Hockey
Puck bounces add light physical randomness
Wii Sports
Minor physics wobble and CPU behaviour randomness
NHL Hockey leans a little harder on optimization, though the gap is small.
NHL Hockey
Exploitable AI angles and line strategy are mappable
Wii Sports
Simple technique tricks like bowling spin 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.