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.

Execution · Twitch Chaos
N64 couch classic where blue shells and shortcuts decide friendships.

Execution · Twitch Chaos
GameCube kart racer with two riders per kart trading items mid-drift.
Mario Kart 64 leans Execution (Twitch Chaos); Mario Kart: Double Dash!! leans Execution (Twitch Chaos).
Mario Kart: Double Dash!! leans a little harder on execution, though the gap is small.
Mario Kart 64
Mini-turbo snaking and shortcut execution
Mario Kart: Double Dash!!
Two-character swaps and drift timing
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Mario Kart 64
Couch rivals bait shells and fakes
Mario Kart: Double Dash!!
Item duels against humans reward baiting
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Mario Kart 64
Item draws swing every race
Mario Kart: Double Dash!!
Special item rolls swing races
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Mario Kart 64
Shortcut and line knowledge is fully mapped
Mario Kart: Double Dash!!
Character pairings and lines are solved
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.