Feel free to use it! (You'd also have to remove the existing use of this._action.subject().removeState(2))
I think it would benefit the plugin because I'm not sure if guarding works correctly the way it's written right now, I'd have to test it out because while it was showing the guard animation, it seemed like it wasn't calculating the effect.
I would also recommend having a note telling players to remove the "Auto-removal Timing" that RPG Maker MV has on by default for the Guard State if you do this, because I think those might conflict with each other.
Ultimately up to you if you use it, but I'd definitely recommend it!