head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is reads, 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 high-execution 3D fighter where reading opponent tendencies and optimising punishment routes defines top play.
Marvel vs. Capcom 2: New Age of Heroes leans Execution (Grand Arena); Tekken 7 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 7
Long combo strings and just-frames demand high motor precision
Tekken 7 leans a little harder on reads, though the gap is small.
Marvel vs. Capcom 2: New Age of Heroes
humans bait assists and mix high-low constantly
Tekken 7
Reading opponent's defensive tendencies and rage art timing is 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 7
No RNG; all information is visible in the match
Tekken 7 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 7
Rage Art/Drive usage, wall carry routes, and frame data heavily studied
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.