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
Futuristic large-scale Battlefield where teams besiege flying Titan carriers.

Execution · Competitive PvP
Cold War-era shooter pairing twitch multiplayer with the cult Zombies mode.
Battlefield 2142 leans Execution (Competitive PvP); Call of Duty: Black Ops leans Execution (Competitive PvP).
Call of Duty: Black Ops leans a little harder on execution, though the gap is small.
Battlefield 2142
Gunplay, piloting, and Titan boarding need solid mechanics
Call of Duty: Black Ops
Gunfights hinge on aim and reaction speed
Call of Duty: Black Ops leans a little harder on reads, though the gap is small.
Battlefield 2142
64-player human teams shift fronts and Titan assaults
Call of Duty: Black Ops
Reading human opponents' positioning and timing
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Battlefield 2142
Large maps hide flanks; battle chaos obscures information
Call of Duty: Black Ops
Spawns, care packages, zombies RNG
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Battlefield 2142
Unlock paths, squad roles, and Titan strategy reward planning
Call of Duty: Black Ops
Class builds, map control, zombies routing
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.