There's a couple of possibilities.
If you want the player to remain solid to bullets while the acrobatic ability is active,
The one on my mind is, have the kinds of objects that can be temporarily not solid (on your collision layer) be different from the objects that are always solid. (e.g, SolidWall and AcroWall)
Your Acrowall would have different animations based on direction and style; "VaultFenceUpDown" "RunWallUp".
Then, when the player character collides with the Acrowall; if they're not in Acrobatics Mode, they just stop.
If they're not going one of the acceptable directions of the acrowall? (Trying to cross the runwall going left or right) they stop.
If they're in Acromode and going the right direction, then,
(Player->8-Direction.StartIgnoringInput)
Then, AcroWall->Solid.Disable
Player.AnimationChange.RunWallUp
Player.8Direction.SimulateInput("Up")
until they're no longer overlapping the Acrowall. Then you reenable Acrowall Solids, 8-Direction input, and normal animation.
Make any sense?