[WebXR] Can a model freely move in AR space?

Questions
1
  1. Can a model freely move in AR space?
  2. Is it possible to control virtual model moving in the AR space by just changing the the pose of its anchor originally attached to the model?
  3. If moving virtual model is out of frames for a while, can we re-gain the model as we come close to it or the model come close to us?
    If I can get the anchor for my placed model, and change the pose of the anchor whatever I want, an other issue suddenly came out of my mind:
  4. Does WebXR have an Animation API for model movement, or
    I could make that animation by common ways in JS (like using setTimeout to change model pose every other second)
    THX for your help!