Hello! Yes, Fornax Animarum is currently limited to heroes in battle. I’m running some tests; having it apply to both the town and battles was accelerating the game and construction, a bit too much.
Regarding the excess XP carrying over to the next level, that’s a great point, thanks for bringing it up!
And thanks for the feedback, I didn’t think anyone would notice that this Arcana wasn’t applying to both Soul channels.