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
Cold War-era shooter pairing twitch multiplayer with the cult Zombies mode.

Execution · Competitive PvP
Precise stick control plus constant adaptation to a human opponent's tactics.
Call of Duty: Black Ops leans Execution (Competitive PvP); Pro Evolution Soccer 2019 leans Execution (Competitive PvP).
Call of Duty: Black Ops leans a little harder on execution, though the gap is small.
Call of Duty: Black Ops
Gunfights hinge on aim and reaction speed
Pro Evolution Soccer 2019
Dribble touch, pass weight and finishing demand precise sticks
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Call of Duty: Black Ops
Reading human opponents' positioning and timing
Pro Evolution Soccer 2019
Human opponents adapt formations and punish predictable patterns
Call of Duty: Black Ops leans a little harder on variance, though the gap is small.
Call of Duty: Black Ops
Spawns, care packages, zombies RNG
Pro Evolution Soccer 2019
Deflections and keeper randomness add bounded chaos
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Call of Duty: Black Ops
Class builds, map control, zombies routing
Pro Evolution Soccer 2019
Tactics, instructions and set-piece routines 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.