I have asked the same question, short of saving the data myself I am not coming up with a better way to do this.

Create an entity and then install gesturesforentity arView.installGestures(.all, for: myEntity)

I am wondering if the same thing is possible for hand joints in a non-skeleton or any joints that are not bodyanchors? I will try this same approach and let you know if it works. If you know how to update a joint already I will gladly pay the courtesy forward.

Sorry I am late but create a an ARSession delegate