head to head
Call of Duty: Modern Warfare 2 asks more than One Piece: Burning Blood, and the gap is execution.

Execution · Competitive PvP
Blockbuster 2009 sequel famous for killstreak chains and frantic multiplayer.

Execution · Competitive PvP
An anime arena fighter testing team-switch timing and counter prediction against humans.
Call of Duty: Modern Warfare 2 leans Execution (Competitive PvP); One Piece: Burning Blood leans Execution (Competitive PvP).
Call of Duty: Modern Warfare 2 leans clearly harder on execution.
Call of Duty: Modern Warfare 2
Fast time-to-kill rewards raw aim and reflex
One Piece: Burning Blood
Combo timing and guard breaks need moderate hands
Call of Duty: Modern Warfare 2 leans a little harder on reads, though the gap is small.
Call of Duty: Modern Warfare 2
Outguessing human rotations and flanks
One Piece: Burning Blood
Human opponents bait switches and counters constantly
Call of Duty: Modern Warfare 2 leans clearly harder on variance.
Call of Duty: Modern Warfare 2
Spawn flips and killstreak randomness
One Piece: Burning Blood
Full-information arena with no hidden state
Call of Duty: Modern Warfare 2 leans a little harder on optimization, though the gap is small.
Call of Duty: Modern Warfare 2
Killstreak economy, loadout and map knowledge
One Piece: Burning Blood
Team composition and Devil Fruit matchups reward study
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.