A:AnswerYes, The airtag will notify the nearest device and tell them they are being tracked or, an airtag (that isn’t theirs) has been around them for a certain amount of time.
A:AnswerIf you still have an old device with the same apple id you connected the airtag to, you can remove the airtag and connect it to another new apple id. Another option is to share the airtag with another apple id from the main device.