You cannot get a list of one post type ordered by a value of another post type. This is not possible use WP_Query.
To do this any value you want to order by must be a value for the posts that you want to order.
What this means is that when you save a post you must use an acf/save_post action to copy the values you want to be able to order by from the other post type and save it as a meta value for the post being saved.
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