You can classify it under any category outlined in the Local Files for Trailers and Extras support article. I personally have found its most consistent and easy for me to manage using the ‘Organized in Subdirectories’ method in that article. I personally found that none of them really fit so I categorize them under ‘Other’.
In regards to the symbolic links, it is different than a shortcut in behavior and creation. I like how it was described in this HowToGeek article which also has some examples of their creation and use:
Symbolic links are basically advanced shortcuts. Create a symbolic link to an individual file or folder, and that link will appear to be the same as the file or folder to Windows—even though it’s just a link pointing at the file or folder.
To simplify it from a high level view: Shortcuts are a special file type all their own. The program must be able to handle the link and all those complications. Symbolic links appear to be the actual target. The OS handles the link and the program thinks it is just handling a local file.
You can read more technical details about symbolic links on Wikipedia.
If you run a list command a shortcut and symbolic link will show differently. When you use a symbolic link Plex is just accessing the file as it normally would and sees it local while the lifting to point it to a different spot is done outside Plex. Symbolic links are especially powerful as you can point to absolute paths, the symbolic link doesn’t even have to point to the same disc on the system, or event that same system! (Don’t hop systems unless required as this adds complexity regarding access, permissions, and availability).
TL;DR Shortcuts are not symbolic links. Shortcuts are for people using GUIs, symbolic links are for software navigating file paths
