I have to be honest, as a huge fan of their trailers since Book 3 of Avatar, I wasn't really impressed by this one. It didn't have the same "oomph" from the previous trailers, especially the Korra Book 3 trailer. Music was god-tier though.
In regards to the animation, the animation of Book 4 was pretty bad, in some ways worse than Book 2 if we ignore B4's finale. Up until the Kuvira vs. Su fight we barely had action scenes, and the ones we did have didn't look that great. Not to mention many shots of static characters with a lack of movement. Compared to Book 1 (which I just rewatched), with incredible fluidity and clarity, Book 4 was awful animation-wise. If people want specific moments I can take the effort to find those as well.