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 · Competitive PvP
Large-scale modern combined-arms shooter built on destructible maps and squad teamwork.

Execution · Competitive PvP
Free-to-play hero shooter where loadout cards customize champions in objective team fights.
Battlefield 3 leans Execution (Competitive PvP); Paladins leans Execution (Competitive PvP).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Battlefield 3
Gunplay, suppression management, and vehicle piloting
Paladins
Hitscan aim and ability timing in firefights
Paladins leans a little harder on reads, though the gap is small.
Battlefield 3
Human teams adapt routes and armor pushes
Paladins
Human teams flank, bait ults, and adapt
Battlefield 3 leans a little harder on variance, though the gap is small.
Battlefield 3
Spawns, destruction, and vehicle drops shuffle engagements
Paladins
Card draft order adds mild run variance
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Battlefield 3
Unlock paths, class synergy, and map control
Paladins
Loadout card builds and item counter-buying
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.