Always use Season xx subfolders when adding external subtiles and other local assets.
After adding external subtitles, you may have to Refresh Metadata at the show level.
The file names in the top screenshot are no conforming to Plex guidelines. All bets are off here.
Plex doesn’t recognise {anidb-10537} as a matching hint. You can only use TheTVDB or TheMovieDB with series.
If you are still using the legacy agents and the custom aniDB agent: that might simply
have stopped working.
it also happens for crash landing on you which uses the default plex agent
the anidb agent also works fine just plex is not adding the subtitles to any of the shows, regardless of agent
That doesn’t matter. Instead of using the terms “public” or “beta”, use the version number.
Particularly because certain beta versions will become the public version at some point.
Avoid confusion, and let the person who is trying to help know, what you are using.