Do you have any examples of this. I'm not sure what you're asking me to do.

Wait on this, as it will need to be financially approved first. 

As for what I am thinking, there are not currently any examples because I have been manually creating a WP Show Post list for each category then manually putting it at the bottom of each page. It's something I do so often that I think it would be worth it to write it in a way that we could use it in our base theme. 

Posts > Category > Edit
Obviously don't remove "Parent Category" but similarly, you would pick a page(s) for these posts to display on. So it would be a list of page selections or they search for the page or whatever, but there would be the option to display on multiple pages.
Then they would be styled similar to WP Show Posts and display at the bottom (below content, above footer) of whatever page(s) they set.

image.png 48.6 KB • Download

OR
On each page, we have it built in that they can add a specific category the same way we add "Add Section". So it would be like Add Section > Display Category. Then they select which category to display. 

Internally, we discussed pulling it in the same way they can add pick what staff to display on the page.

Approved 11/27
Cost Approved for 6 hours ($300) to make the event categories display at the bottom of the page

As far as I understand this task, they want to have a post slider at the bottom of posts that they will be able to select the category of via an ACF Select (which would be dynamically populated based on their categories).