The current implementation of shown with foreign audio does not work with forced subtitles unless you set the “prefer audio tracks in” option to your primary language.
The problem with this is that it will break other libraries where you want a different primary language. The big one for most people here would likely be Anime.
Is there a reason the setting “shown with foreign audio” flag doesn’t just set forced subtitles to enabled by default with matching language between audio and forced subtitle?
The only other option for this to work is to let us have per-library language options.
Example 1: If you run these settings, all subtitles get enabled. (I assume because it’s showing subtitles with foreign and EVERYTHING is foreign to a language preference of “none”)

Example 2: If you run these settings, every file gets english audio regardless of track defaults, but everything technically “works” as far as subtitles goes.

Example 3: If you run these settings in an attempt to keep japanese as the primary language globally (assuming only anime has a japanese track), Forced subtitles don’t get enabled for English movies.

Example 4: If you run these settings, nearly everything works by default. The only thing that never gets enabled is forced subtitles. If we could get forced subtitles enabled when the audio language matches the forced subtitle track, this would be perfect.
(the preferred audio language doesn’t seem to matter in this. I can set it to “none” and get the same result)

I can’t seem to find a combination of settings that works with my use case.
Is there a reason that the forced track flags aren’t being respected in any of the options other than when you specify an audio preference and tick the box to automatically select tracks?
Is there any way we can get Example 4 to enable forced subtitles for matching audio + forced sub?
Emby doesn’t have these subtitle issues and I wish that Plex didn’t either. This is one of those things that can and will push people towards another application.