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 · Practiced Mastery
An arena fighter mixing combo execution, build grinding and human prediction online.

Execution · Competitive PvP
Reversal-timing wrestling that becomes a prediction game against humans.
Dragon Ball: Xenoverse leans Execution (Practiced Mastery); WWE SmackDown! Shut Your Mouth leans Execution (Competitive PvP).
Dragon Ball: Xenoverse leans a little harder on execution, though the gap is small.
Dragon Ball: Xenoverse
3D arena combos, vanishes and ki management need practiced hands
WWE SmackDown! Shut Your Mouth
Grapple timing and reversals reward quick hands
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Dragon Ball: Xenoverse
Online PvP rewards predicting human mixups; PvE is scripted
WWE SmackDown! Shut Your Mouth
Versus friends, reversal baiting becomes a prediction game
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Dragon Ball: Xenoverse
Skill drops from missions roll randomly
WWE SmackDown! Shut Your Mouth
Mild AI and momentum randomness
Dragon Ball: Xenoverse leans a little harder on optimization, though the gap is small.
Dragon Ball: Xenoverse
Build crafting and attribute allocation shape PvP viability
WWE SmackDown! Shut Your Mouth
Move-set knowledge and momentum management 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.