The description of Acid Splash says (emphasis mine):
Range 30 feet; Targets 1 creature
You splash a glob of acid that splatters your target and nearby creatures. Make a spell attack. If you hit, you deal 1d6 acid damage plus 1 splash acid damage. On a critical success, the target also takes 1 persistent acid damage.
There is no radius for the area of effect (AoE) listed for the splash unto nearby creatures. I also couldn't find any general rules for splash effects of spells (all I could find was for bombs). Note also, that Acid Splash does not have the 'Splash' trait.
What is the AoE of the splash damage of Acid Splash (if any)? Is the target also hit by the splash damage?