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

Execution · Practiced Mastery
The fan-favourite sequel with harder levels and deeper secrets.

Execution · Practiced Mastery
A blistering DS Sonic built around the boost gauge, introducing Blaze the Cat.
Donkey Kong Country 2: Diddy's Kong Quest leans Execution (Practiced Mastery); Sonic Rush leans Execution (Practiced Mastery).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Donkey Kong Country 2: Diddy's Kong Quest
Demanding jump chains and animal-buddy control
Sonic Rush
Boost management and trick timing at high speed
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Donkey Kong Country 2: Diddy's Kong Quest
Fixed enemy patterns, no adaptation
Sonic Rush
Scripted bosses only
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Donkey Kong Country 2: Diddy's Kong Quest
Secret Lost World entrances hidden until found
Sonic Rush
Dual-screen layouts surprise on first runs
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Donkey Kong Country 2: Diddy's Kong Quest
Routes, DK coins, and bonuses fully mappable
Sonic Rush
Rank grinding turns levels into solved boost routes
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.