head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is optimization, 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
A tag-team 3D fighter layering team optimization onto Tekken's execution and reads core.
Tekken leans Execution (Competitive PvP); Tekken Tag Tournament leans Execution (Grand Arena).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Tekken
Frame-tight inputs, juggle combos, movement demand trained hands
Tekken Tag Tournament
Tag combos and netsu juggles demand precise inputs
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
Tekken Tag Tournament
Tag timing adds another layer of human mind-games
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
Tekken Tag Tournament
Open information; nothing hidden between rounds
Tekken Tag Tournament leans a little harder on optimization, though the gap is small.
Tekken
Frame data, punishes, and combo routing are studyable systems
Tekken Tag Tournament
Team synergy and tag combo routing are optimizable systems
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.