You know that the artist has posted a recording of him painting of one of the pre-animation stills?
Putting aside that it's not the same char and this wasn't used in the video, this looks nothing like what's in this video. The style's quite different. It wouldn't surprise me if they did some work on the stills and had AI color it then clean up any mistakes. Raiden Shogun is super popular, so it's not like there's not enough art for models to be trained about her. The 3rd scene specifically has the strongest AI feel to it.
Putting aside that it's not the same char and this wasn't used in the video, this looks nothing like what's in this video. The style's quite different. It wouldn't surprise me if they did some work on the stills and had AI color it then clean up any mistakes. Raiden Shogun is super popular, so it's not like there's not enough art for models to be trained about her. The 3rd scene specifically has the strongest AI feel to it.