You need to name them all correctly or move the incorrectly named episodes out of the view of the Plex scanners.
Then Plex Dance the show.
Which folder is added to the TV show library?
Given the screen shots, it should be:
.../tv shows <-- folder added to tv show library, name unimportant
..../Kolchak The Night Stalker (1974) <-- showname (intro year)
....../Season 01
......../Kolchak The Night Stalker (1974) s01e01 The Ripper.ext <-- ext = mkv/mp4/etc.
Tools to help with renaming:
Filebot is popular. The free version of Tiny Media Manager works quite well. There are many others as well.
TMM Renamer Patterns:
- Show Folder Name:
${showTitle} (${showYear}) {tmdb-${showTmdb}}
- Season:
Season ${seasonNr2}
- Episode Name:
${showTitle} (${showYear}) s${seasonNr2}e${episodeNr2} ${episode.title}
- Movie Folder Name and Movie Name:
${movie.originalTitle} (${year}) {tmdb-${movie.tmdbId}}
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