>>15179760each character can only use one at a time, but they can have between 4-8 pokemon on their team, which you can change
the more you use a party member the better your synergy becomes. it's literally called your link with that pokemon, and every character has a different max link with each pokemon and are completely incompatible with others.
the party you want to use has to follow you around to use them in the kingdom battles while all the others stay at your other kingdoms (clubhouses) doing shit you tell them to (train, make money, find more potential party members)
'evil team' (armies) changes in each story, some are stupidly difficult and others are pathetically easy. nobunaga's army was a pain in the ass in most stories, i'd be surprised if anyone ever had a problem with motonari.
that's everything you asked for, it's just in a tactics format instead of double battles.
