Persona is a spinoff much like Mario Kart is a spinoff when people say 3D Mario for instance they're not including the likes of MK or other spinoffs and it's been the same for Persona for a while now. $ sales may not be an complete metric but it gives us the range in which the game is performing as ultimately surpassing pass games would indicate sales are either in range of them or higher, considering it came in 6th on the platform in the month as well in a window that included Pokemon, SMP and Just Dance with the only other two games above it being ACNH and MK8D it's fair to say it did well, SMTIV on 3DS in comparison released in July with little competition for consumer interest the biggest release on 3DS during the month was Shantae.