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
The 3D fighting series opener where execution and human mind-games decide every round.

Execution · Grand Arena
Frame-perfect execution fused with constant prediction of an adapting human opponent.
Tekken leans Execution (Competitive PvP); Ultra Street Fighter IV leans Execution (Grand Arena).
Ultra Street Fighter IV leans a little harder on execution, though the gap is small.
Tekken
Frame-tight inputs, juggle combos, movement demand trained hands
Ultra Street Fighter IV
One-frame links and FADC timing set a brutal hands ceiling
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Tekken
Human opponent adapts; throws, lows, sidesteps form mixup mind-games
Ultra Street Fighter IV
Footsies and conditioning the human opponent is the core duel
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Tekken
No hidden info; only matchup unfamiliarity early on
Ultra Street Fighter IV
Almost nothing hidden once both characters are known
Ultra Street Fighter IV leans a little harder on optimization, though the gap is small.
Tekken
Frame data, punishes, and combo routing are studyable systems
Ultra Street Fighter IV
Frame data, matchups and option-selects form deep studied theory
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.