[Help]kill or template

At the current moment I’m trying to make a toggled buff that changes your actor/player mesh/texture/animations. (Once one you look like a monster or something and when toggled off you change back) I tried to make a custom template but dbr editor errors saying " Object reference not set to an instance of an object". Any Help or Ideas on if what i’m trying to accomplish is even do able.

You can overlay the player mesh by a static one but without animations and the monstermesh needs to cover the player mesh as it does not vanish.

Making own templates makes no sense since there will be code missing to back up the new template class.

Thank you, for the information and help.