You can get it here: https://amzn.to/3q2rO6J
It is 160 pages book with beautiful illustrations from development art, character sketches, storyboards, and color scripts. It features colorful concept art from the all-original fantasy adventure and also includes fascinating facts and details from the creators.
Previously published artbooks:
Art of Soul - official artbook for Disney Pixar Soul animated movie
The Art of Frozen 2 Facebook