I have Plex running on my Synology NAS and I am able to see all my content that I upload except for Seasons 10 (only see one episode) through 13 of King of the Hill.
The naming is the same for all seasons and episodes, so I don’t know why most show on Plex but those seasons don’t.
There are subfolders for each season named Season 01, Season 02…Season13.
Episodes within each season folder are named:
in Season 10
1001 - Hank’s On Board.mkv
1002 - Bystand Me.mkv
same format in the other seasons…
I have done a refresh on the metadata and done a rescan on library files.
Follow Plex naming requirements, then Plex Dance the show.
/TV Shows <- Folder added to TV Show library, name does not matter
.../King of the Hill (1997) <- Show_Name (year)
....../Season 10 <- "Season" in English, two digits for year
........./King of the Hill (1997) - s10e01 - Hank's on Board.mkv <- sXXeYY required
Many people use Filebot. It is quite powerful and can rename an entire library in minutes.
Tiny Media Manager is also very useful, and free. I’ve used it on several movies with the pattern ${title} (${year}) {imdb-${imdb}}. You can easily set a pattern for TV shows that matches Plex’s naming standards.
PowerRenamer in Microsoft Power Tools is helpful for simple renaming with pattern matches or regular expressions. It makes quick work of tasks such as adding a year to file names, removing undesirable text from multiple files, etc. Simple example: Rip a TV show with MakeMKV and all the episodes have _tXX at the end. You can remove it from all episodes in just a few seconds.