When you use the current advanced filter e.g. on TV shows, on a specific audio language e.g. German it will display all TV shows that contain any German audio track, but not only. If a show has e.g. 3 episodes with English only audio tracks and 3 with German as well as English audio tracks it will show all 6.
Can you make a filter that will only show the video files with a German audio track?
A filter of that complexity will probably never be available in Plex.
For library curation purposes, here’s what you can do right now:
Use WebTools NG to export a CSV file with many more details about your library than is easily available in the Plex GUI.
Open this CSV file in a spreadsheet application.
Use the sort and filter features of the spreadsheet app to filter out the files which match your criteria.
