Yukari (from Persona 3) and Chie (from Persona 4). Yukari is very outspoken and has a bit of a sarcastic side, while Chie is energetic and a bit of a tomboy. Their different personalities could lead to some really fun and comical interactions, especially when they're facing Shadows together or just hanging out in the school setting.
Junpei (Persona 3) and Yosuke (Persona 4) would make an interesting pair. They are both the 'best friend' characters in their games. Junpei's clumsy yet brave nature combined with Yosuke's laid - back but sometimes insecure personality could create some hilarious and heartwarming moments as they support each other in battles and in understanding the new world they find themselves in during the crossover.
Yu Narukami and Joker would be an interesting pairing. Yu is the calm and collected leader of the Investigation Team, while Joker is the charismatic leader of the Phantom Thieves. They could exchange ideas about leading their respective groups and how to deal with the Shadows. Their different fighting styles and Persona abilities could also make for some great team - up moments in battle.
Chie Satonaka from Persona 4 and Ann Takamaki from Persona 5. They both have strong personalities and are very passionate about their causes. Chie with her love for kung - fu and Ann with her modelling career. They could bond over their determination and share their combat skills and life experiences with each other. It would be fun to see how they interact in a crossover scenario.
Ruby and Yu Narukami. Ruby is young and full of energy, always eager to fight for what's right. Yu is a calm and collected leader. Their different personalities would make for an interesting dynamic. Ruby could learn from Yu's more methodical approach to problem - solving, while Yu could be inspired by Ruby's unwavering determination.
Makoto Naegi from Danganronpa and Yu Narukami from Persona. Makoto's determination and leadership skills could pair well with Yu's calm and collected nature. They could work together to solve the mysteries that occur when their worlds collide.
Akira and Minato would be an interesting pairing. Akira, with his leadership skills as the leader of the Phantom Thieves, and Minato, the protagonist of Persona 3, could share their strategies in combat and dealing with the Metaverse. They both have different experiences with their respective groups, so they could learn a lot from each other.
Jonathan Joestar and Yu Narukami could be an interesting pairing. Jonathan's noble and chivalrous nature would contrast with Yu's more modern and relatable personality. They could learn from each other's sense of justice. Yu could teach Jonathan about the modern world and how to use some basic technology, while Jonathan could inspire Yu with his unwavering determination in the face of danger.
Ruby and Joker could be a great pairing. Ruby's enthusiasm and determination combined with Joker's cool - headed leadership skills would make for an interesting dynamic. They could learn from each other's combat styles and ways of thinking.
Akira and Giorno would make an interesting pairing. Akira has his leadership skills and the ability to use Personas, while Giorno has his determination and powerful Stand, Gold Experience. They could learn from each other's sense of justice and different ways of achieving their goals. Akira could teach Giorno about the power of the collective, as the Phantom Thieves work as a team, and Giorno could show Akira how to be more assertive and decisive in his actions.
One popular pairing is Joker with characters from the Persona series like Akechi. Their complex relationship in the game makes for interesting crossovers. Another is Joker with characters from other RPGs, such as Link from The Legend of Zelda. It's cool to see how their different abilities and personalities interact. Also, Joker and characters from the Final Fantasy series like Cloud are quite popular.
Maybe the Velvet Room attendants from both games somehow get their worlds mixed up. Igor from Persona 5 and Margaret from Persona 4 have to work together to set things right. This leads to the characters from both games interacting. The Phantom Thieves might learn some new combat techniques from the Investigation Team and vice versa. They could then use these new skills to face a common threat that emerges from the merging of their two realities.