As stupid as this sounds I feel like its something that could have been created at some point.
In otherwords you have a friend over, and you form two teams of units to fight each other with
Pass-N-Play is of course when you have two people who pass the controller for each of their turns or even two controllers I suppose.
edit: I searched before making the topic but i mostly just got things on AI arena and people asking about online multiplayer.
There is debug mode. Take a look at gameshark handbook on GameFaqs I guess.
Ah that is super useful and I suppose it will have to do if there are no alternatives. Thank you very much!
world debug code is awesome for that :D
Just note that it only does 4v4 (or less -- which is fine, there's a limit of 9 sprites so 5v5 just looks horrible) and works off the same memcard so if both you and a buddy want the same unit you'll need to duplicate it (either with fftastic or gameshark).