Usually if it is moving then it has to spend energy to do so, sometimes it's not likely to take food at that time, you can try, but don't get discouraged if it doesn't take it, at least not right away.
For now you can try to feed it some small meaty foods with a clean turkey baster (get one just for your tank), then you can thaw some mysis shrimp out and try feeding it. If it doesn't take it now then wait until lights out and see if it will accept it. If not then give him a couple more days before trying again.
Also BTA's sometimes head straight for the back of the tank, if it does then it will most likely id itself.
Its annoying but they do it when new to a tank.
Moving is a way to find the right spot for it, nothing we do will change that, it will decide, not us. Which is sometimes another annoying habit of the BTA or any anemone.
Thomas