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

Execution · Competitive PvP
Shot timing and play-calling against opponents who scheme around your habits.

Execution · Competitive PvP
Tests arena brawling timing and skill-build crafting against human opponents.
NBA 2K16 leans Execution (Competitive PvP); Sonic Battle 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.
NBA 2K16
Shot-stick timing and dribble moves gate every possession
Sonic Battle
Aerial juggles and guard timing on a grid arena
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
NBA 2K16
Online opponents adjust defensive schemes against your tendencies
Sonic Battle
Versus humans, baiting special skill choices is the edge
NBA 2K16 leans a little harder on variance, though the gap is small.
NBA 2K16
Shot RNG and card packs add bounded randomness
Sonic Battle
Little randomness beyond skill-card drops
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
NBA 2K16
Playbooks, rotations and roster building reward deep study
Sonic Battle
Custom skill builds for Emerl define the meta
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.