head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is optimization, and it is a single point.

Execution · Competitive PvP
Retro international football sim with team management basics.

Execution · Competitive PvP
Shot timing and play-calling against opponents who scheme around your habits.
Football International leans Execution (Competitive PvP); NBA 2K16 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.
Football International
passing and shooting input precision
NBA 2K16
Shot-stick timing and dribble moves gate every possession
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Football International
reading human opponent's attacking patterns
NBA 2K16
Online opponents adjust defensive schemes against your tendencies
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Football International
minor bounce and ref randomness
NBA 2K16
Shot RNG and card packs add bounded randomness
NBA 2K16 leans a little harder on optimization, though the gap is small.
Football International
formation and substitution strategy
NBA 2K16
Playbooks, rotations and roster building reward deep 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.