The only prerequisites would be the individual skills of each Meister and Weapon. If they're already a team, than it's a bit easier for the teacher, but since just about all of them are older and have been in more dangerous fights, their partners might not have come back from battle, leaving just the one. Those odd ends would be teamed up with a compatible soul.

As for Academic requirements, I think that they would have to have a good understanding of many things, but still have some things to learn and master.