The Plex Media Player app does not show the option to skip intros of shows. However it’s available in almost all other clients (see the related support article for the full list).
One step at a time, please.
Do your shows meet the criteria?
Library is configured to scan for intros
If you have configured your server to generate intro markers as scheduled job (vs. doing so immediately when new content is added) – did you give your server a few days to process them during the night?
intros are more than 20 seconds long
intros are ending in the 1st half of the episodes
If you’re not sure about #2:
Open the tv show library in Plex Web and drill down to the episode of a show which doesn’t allow you to skip intros
Click ⋮ > Get Info on one of that episodes
Click View XML
Check if there’s an element named <Marker> with an attribute type="intro"
and i also tried to trigger the skip intro identification with analyzing the show and even the episodes… the activity cylce on the right top shows up and it says “looking for intros” (or so i translated it from german)