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
A tennis simulation where timing execution and reading opponent tendencies drive competitive outcomes.

Execution · Competitive PvP
Blockbuster 2009 sequel famous for killstreak chains and frantic multiplayer.
AO Tennis 2 leans Execution (Competitive PvP); Call of Duty: Modern Warfare 2 leans Execution (Competitive PvP).
Call of Duty: Modern Warfare 2 leans a little harder on execution, though the gap is small.
AO Tennis 2
Ball timing and serve placement have clear skill ceilings
Call of Duty: Modern Warfare 2
Fast time-to-kill rewards raw aim and reflex
Call of Duty: Modern Warfare 2 leans a little harder on reads, though the gap is small.
AO Tennis 2
Online human opponents create adaptive rally patterns
Call of Duty: Modern Warfare 2
Outguessing human rotations and flanks
Call of Duty: Modern Warfare 2 leans a little harder on variance, though the gap is small.
AO Tennis 2
Very little luck in outcomes
Call of Duty: Modern Warfare 2
Spawn flips and killstreak randomness
Call of Duty: Modern Warfare 2 leans a little harder on optimization, though the gap is small.
AO Tennis 2
Player builds and tactical shot variety are learnable systems
Call of Duty: Modern Warfare 2
Killstreak economy, loadout and map knowledge
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.