You should have it in both your pawn and the anim blueprint.
You would set the value in your anim blueprint from the value in the pawn using Get Pawn Owner, and casting to your pawn, as below: (this is the anim blueprint)
Then you can use it like this (in the anim blueprint still):
Say you had a shooting state, depending on what weapon was active in the pawn, it would switch to use a different animation here