I couldn’t find a concrete answer for this. Attempts to recreate the art style of this game correctly have failed, as seen on posts on Reddit. In particular , in almost all Reddit posts made by users claiming to draw in the art style of this game, the art style doesn’t resemble the actual art style properly.
The art of Hades is really detailed. Definitely not something one can easily recreate unless they’re very talented. The way Supergiant uses shading is also very unique, sort of reminding me of Hellboy comics.
That said, there has been some accurate fanart out there. Here’s one by /u/Blindster13