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 · Competitive PvP
A Crash Bandicoot party collection of competitive arena minigames for up to four players.

Execution · Pure Mechanics
Reaction-speed platform racing where shifting colours keep redrawing the level under you.
Crash Bash leans Execution (Competitive PvP); Runbow leans Execution (Pure Mechanics).
Runbow leans a little harder on execution, though the gap is small.
Crash Bash
Minigame timing, mashing, and dodging decide most rounds
Runbow
Fast platform racing through vanishing platforms is pure reaction
Crash Bash leans a little harder on reads, though the gap is small.
Crash Bash
Human rivals in versus minigames can be baited
Runbow
Light jostling with human racers, but little deep prediction
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Crash Bash
Item drops and arena randomness swing rounds
Runbow
Colour swaps and party chaos randomise each race
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Crash Bash
Light minigame strategies, quickly learned
Runbow
Minimal systems - momentum tricks and level memory only
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.