Plex has a “edition” tag that allows you to maintain different versions of a film and the software treats them as the same but separate titles (excellent feature, such as “Gladiator (2000){edition-Extended}” and “Gladiator (2000){edition-Theatrical}”), what I noticed, in conjunction with local extras, if you place two or more files in the same folder with differing feature tags then try to add user/local extras like featurettes or behind the scenes, that neither film will pick those up after a scan or meta refresh. You must separate them into separate folders movie folders.
I suggest you allow multiple films of different editions to store under one folder, and then the local feature/trailers/behind the scenes/etc. can be shared between both, and appear between both. As of now, the current implementation requires creating different folders for each edition of a title then duplicating the extras into each folder.
For example, the folder structure may look like this:
…/Media/Movies/Gladiator (2000)
…Gladiator (2000){edition-Theatrical}.mkv
…Gladiator (2000){edition-Extended}.mkv
…/Featurettes
…The Making of Gladiator.mkv
Then either instance of the title is presented on the movie page with the extra in the extra list, no need to duplicate folders and files.
Thanks!