Bone local space alpha?

Is there a way to apply an additive animation in the local space of a specific bone?

I’ve got a control bone for holding the player’s gun, and I want a fire animation that recoils by rotating the gun up slightly. I have a local space additive animation for this.

When I apply the additive, everything works as expected, and the gun fires with the recoil anim. But when I aim to the side (transitioning to an aim offset pose), the anim stops working.

Or, more specifically, the anim works, but in mesh space; when facing forward, the gun kicks up, but when facing to either side, it rolls away, applying the designated rotation relative to the player’s root, rather than the current local space position of the gun.

Is there a way around this, short of generating a duplicate aim offset that contains the fire anim for every aim pose? It feels like there OUGHT to be a way to make this work, but I would have thought that a local-space additive animation was basically designed to handle this situation.

EDIT: so far, the only thing that works is applying the additive BEFORE applying the aim offset. But that’s a no-go, because I need to apply certain Transform Bone nodes AFTER the additive (to keep the gun from lerping weirdly due to how Aim Offsets interpolate).

I’m pulling my friggin’ hair out over this; I cannot IMAGINE that I am the first person to attempt to apply an aim offset pose and then apply an additive fire animation to it. This seems like Unreal Engine bread-and-freakin’-butter, how could it POSSIBLY be this difficult to do something so simple? Apply a simple recoil rotation to a gun that remains correct regardless of the gun’s orientation in component space. That should be two clicks. Am I going insane?