Is ninten the same person as ness?

No, Ninten and Ness are not the same person, but they are both protagonists from different games in the EarthBound series, which is part of the larger Mother franchise. Ninten is the main character in the game "Mother," while Ness is the protagonist in "EarthBound" (Mother 2). They share similar abilities and themes, but they exist in separate narratives and settings.