Spring River Flower Moonlight Night (2020)

Both have a bromance between a fox spirit disguised as a human man and a human man. Both are set within a dark and magical historical world of creatures and demons.

Similar plot about ghost and human story

Both has a human ghost relationship
Hankiz omar and Eleanor Lee both ghost and flirty

The bromance in Soul Snatcher is just as strong as the one in The Untamed. Give Soul Snatcher a try, it is a feel good movie that will relax you and leave you feeling light.
Warning : Soul Snatcher is not a BL, only a bromance. So if you are looking for a title that only has a BL relationship at it's center then Soul Snatcher may not be for you. However, I suggest you try it as something about the movie is so simple and beautiful it will move you. Kind of like watching a nice Disney movie, like tangled.

They include fox spirits. Bai Qian is a white fox who goes to practice in Kunlun mountain.

Bai Shisan is a red fox who has to find the elixir in Wang Zijin’s body and take it away.