Yeah, I mean editing the .sav files. I have found sections that correspond to each save slot, but I haven’t fully figured out how characters are recorded.
I see a lot of similarities to this post: [FE8] Save Data and Suspend Data Space Allocation
And some of Nintenlord’s notes look useful on character data structure, though I haven’t quite managed to match them with what I’m seeing yet.
But yeah, I wondered why there wasn’t an editor already, given the tremendous amount of other hacking that exists.