Bringing this back since its a big revelation
Latias in this episode used Safeguard, which was the only move Latias knew in the movie. The animation is exactly the same as well, which is a super specific detail for them to randomly bring back. Usually the anime doesn't care to duplicate how a move looks years later. This is more evidence that his is M05 Latias
https://bulbapedia.bulbagarden.net/wiki/Latias_(M05)