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
Territory control through shooter execution and constant prediction of adapting human teams.

Execution · Competitive PvP
A movement-first multiplayer shooter where parkour aim duels decide fights.
Splatoon leans Execution (Competitive PvP); Titanfall leans Execution (Competitive PvP).
Titanfall leans a little harder on execution, though the gap is small.
Splatoon
Aim, swim-form movement and ink management are constant demands
Titanfall
Wall-running gunfights demand elite aim and movement
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Splatoon
Human opponents adapt flanks and pushes every match
Titanfall
Human pilots adapt positioning and titan timing against you
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Splatoon
Hidden squids in ink create momentary information gaps
Titanfall
Some uncertainty in titan drops and flanks
Splatoon leans a little harder on optimization, though the gap is small.
Splatoon
Weapon kits, map control timing and gear builds reward study
Titanfall
Loadouts and titan timing are a thin solvable layer
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.