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 · Practiced Mastery
The original 2003 WWII shooter built around cinematic squad set pieces.

Execution · Practiced Mastery
A modern Gears entry spanning campaign, Horde, Escape, and ranked versus.
Call of Duty leans Execution (Practiced Mastery); Gears 5 leans Execution (Practiced Mastery).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Call of Duty
Aim and reaction carry the scripted firefights
Gears 5
Movement tech and shotgun duels remain the core test
Gears 5 leans a little harder on reads, though the gap is small.
Call of Duty
Light multiplayer prediction; campaign AI is scripted
Gears 5
Ranked versus rewards out-thinking human opponents
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Call of Duty
Some spawn and hit unpredictability
Gears 5
Escape and Horde inject some run variance
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Call of Duty
Memorising set pieces and weapon positions
Gears 5
Character ultimates and map control are learnable
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.