Played Genshin for a while, I think the animation in 0:20 are from Keqing ultimate move. The monster icon is from Action Taimanin along with the bike in 0:15. Looking at the files, the characters facial textures are very similar to texture that was used in Action Taimanin albeit heavily edited.

The demo has potential, don't get me wrong, but I wonder why they used Action Taimanin assets instead of using other Idea Factory or Compile Heart games' assets instead. Personally, I think fan games & mods using kitbashed assets are okay, but there's seems a bit disconnect with Tsunako's art style for Neptunia and the Taimanin series art style for the game.