At first I thought this was a condensed alternate retelling of the Legend of White Snake main story, but by the end they make it obvious this is a prequel, this is just a "past life" of our main characters. The main story is what you can see in the 36-episode 2019 TV series "The Legend of White Snake".
The CGI here is excellent in terms of still-image look, but when animated it suffers from excessive speed, especially during combat scenes, and from a lack of weight of most characters and objects - everything lands like a feather on top of everything else, there is no impact, nothing has weight, which makes it less believable. Then there are some weird choices with oversexualizing the female characters in some scenes, and even the male character at one point, even though it's supposedly done as a joke. OTOH there was also some Disney-style comic relief thrown in, which also seemed out of place in an essentially Chinese production.
The plot is not too coherent or compelling but it works, and the main love story is also unconvincing, with no real chemistry between the two, but for me this was fine - I had already seen the main story in the TV series, and that had more than enough chemistry going on, and in a perfect family-friendly winter season PG-13 type presentation.
"Bai She 2" from 2021 you can just ignore, it's a complete perversion with cars and motorcycles, the true sequel to this movie is the 2019 Legend of White Snake TV series.