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 · Pure Mechanics
Tests NES-hard execution and rote memorisation of brutal fixed stages.

Execution · Pure Mechanics
A boss-rush action game that is nothing but execution tests against scripted duelists.
Battletoads / Double Dragon leans Execution (Pure Mechanics); Furi leans Execution (Pure Mechanics).
Furi leans a little harder on execution, though the gap is small.
Battletoads / Double Dragon
Unforgiving brawls and vehicle stages punish any input slip
Furi
Parry timing, bullet dodging, and duel precision
Furi leans a little harder on reads, though the gap is small.
Battletoads / Double Dragon
Enemies run fixed NES-era scripts
Furi
Bosses are scripted patterns, however adversarial they feel
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Battletoads / Double Dragon
Everything is deterministic once stages are memorised
Furi
Fixed boss sequences
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Battletoads / Double Dragon
Memorising stage layouts and enemy spawns is mandatory progress
Furi
Learning each boss's phases converges to mastery
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.