This is a film that is over two hours long. Most of it is people emoting with their faces without doing anything, moving slowly, talking slowly. The rest is a bit of Wire-fu and CGI and a lot of knowledge lost in translation. That doesn't make it a bad film, because the production values and acting were good, while the story is a combination of murder mystery, detective story, love drama and monster flick. Yeah, it goes all over the place. It's just slow.
Moreover, a lot of other reviewers took the story to be about the love between the master and the empress, but to me it felt like it was more between Qing Ming and Bo Ya. Certainly they had the more romantically long face emoting moments. And that ending!
Anyway, there is a lot of stuff lost in translation for a Westerner. Even if we don't need to understand the mechanics of the magic, or the spirit servants, or the giant snake, we can get the overall idea for the story. But as many other people said, what you see translated in the English subtitles is also not enough to understand what the people are talking about, certainly not the finer metaphorical and cultural aspects of the dialogue.
Bottom line: I watched this on the TV app, which doesn't have a speed setting. Netflix! Make the speed setting available everywhere!! Did I mention the film feels really slow?