According to the information from Steam and PlayStation Store, it seems like Dragon Ball: Sparking Zero might not have local multiplayer.
It looks like Dragon Ball: Sparking! ZERO lacks offline multiplayer
Dragon Ball: Sparking Zero Sounds the Alarm of a Dying, but Beloved Feature
This is for naruto connections and sparking zero. Naruto says single player, but you CAN do offline multiplayer. So hopefully same deal 🤞🤞 : r/tenkaichi4
the new Budokai Tenkaichi does not support local PvP. Only online PvP. The best memories I have playing BT3 were with my friends playing the world tournament on the PS2. : r/Dragonballsuper
Dragon Ball: Sparking Zero Sounds the Alarm of a Dying, but Beloved Feature
Dragon Ball: Sparking Zero Reportedly Won't Include A Split-Screen Mode
Contrary to some people belief, I think we will definitely get local co-op. This is the image from the trailer. : r/tenkaichi4
This Is A Mistake Dragon Ball: Sparking! Zero
DRAGON BALL: Sparking! ZERO Xbox Series S - Best Buy
Dragon Ball Sparking Zero might not have Local Multiplayer. : r/GamingLeaksAndRumours
NEW LEAKS!! LOCAL MULTIPLAYER TRADED FOR CROSS PLATFORM?! DRAGON BALL SPARKING! ZERO
Dragon Ball Sparking Zero : r/tenkaichi4
Dragon Ball Sparking Zero - IGN
New Budokai Tenkaichi is called Dragon Ball Sparking Zero, Super Broly and more confirmed, Page 5