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 · Grand Arena
Chaotic tag fighter whose top tiers reward blistering execution and assist mastery.

Execution · Grand Arena
A tag-enhanced Tekken that multiplies execution demands and opponent reads by adding partner management to every exchange.
Marvel vs. Capcom 2: New Age of Heroes leans Execution (Grand Arena); Tekken Tag Tournament 2 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.
Marvel vs. Capcom 2: New Age of Heroes
infinite combos and assist timing demand elite hands
Tekken Tag Tournament 2
Tag combos and partner launcher extensions demand high motor precision
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Marvel vs. Capcom 2: New Age of Heroes
humans bait assists and mix high-low constantly
Tekken Tag Tournament 2
Tag crash timing and incoming character reads against humans are constant
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Marvel vs. Capcom 2: New Age of Heroes
fully deterministic engine
Tekken Tag Tournament 2
No RNG; all information is visible
Tekken Tag Tournament 2 leans a little harder on optimization, though the gap is small.
Marvel vs. Capcom 2: New Age of Heroes
team order, assist synergy, and matchup knowledge
Tekken Tag Tournament 2
Tag team pairings and shared health management reward deep preparation
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.