I'll phrase it like this as someone who played Persona first with P3P.
You know those overworld sections in 5, take that, and just make it into a really basic screen like you were playing a GBA game with an 'overworld' where it is just set points. Everything else is more or less the same, the dungeon crawling is still movable and it is effectively like mementos. You lose a decent bit of immersion, but it isn't the worst as the more interesting setting is still the same aka the maze dungeon area with all the enemies. It will make the social links so much faster as a small plus because you don't have to move around a map.
Laura Bailey plays the female protagonist in P3P, so they're basically like Joker in P5.