You could try using one of the Orb item abilities that have the Enabled Attack Index field. But I don't remember if that changes the unit's attack UI, and the method is quite tricky to make function properly.
I'm on a page about incorrect corrections, and spent the better part of like two hours trying to get someone to understand that -5^2 = -25, not 25, and then that post had comments get reposted because that group is self sustaining, and that person was in turn trying to explain what I just explained to them. And I'm taking that as a victory