Problem: I have two custom post types - Characters and Photographs - linked in a post relationship. The Photographs CPT has a custom taxonomy Photoshoots, with terms for each Photoshoot assigned to each Photograph. In the template for Characters posts, I would like to display a list of all Photoshoots terms applied to all Photographs posts related to the current Character post.
Solution: The problem does not have a straightforward solution, because you need to filter a View of taxonomy terms by the properties of a related post type. The best solution requires you to use the legacy Views editor to create a nested View structure that produces the desired terms list.
See step-by-step instructions in the following comment: https://toolset.com/forums/topic/taxonomy-view-6/#post-2101763
