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
Wrestling-style timing duels with grapple prediction against human opponents.

Execution · Competitive PvP
A crossover anime arena fighter pitting Shonen Jump heroes against each other.
Def Jam Vendetta leans Execution (Competitive PvP); Jump Force leans Execution (Competitive PvP).
Def Jam Vendetta leans a little harder on execution, though the gap is small.
Def Jam Vendetta
Grapple timing and reversal windows demand sharp inputs
Jump Force
3D arena combos with generous tracking
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Def Jam Vendetta
Human matches turn on predicting grapples versus strikes
Jump Force
Human opponents force guard-break guessing
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Def Jam Vendetta
Nothing hidden once movesets are learned
Jump Force
Full information arena duels
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Def Jam Vendetta
Character move pools and reversal systems are mappable
Jump Force
Team picks and awakening meter management
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.