I’m able to find TV skills for Alexa, but none of them (that I can see) will check the schedule and remind you of your favorite TV shows. I know I can set a reminder for them, but if the show time changes or the season ends, I don’t want to have to edit every reminder. Is there a skill that does this? Or maybe is it possible to create one?
I'm not aware of any already existing skills, but building one should be possible with the latest API which supports alarms/alerts https://developer.amazon.com/docs/alexa-voice-service/alerts.html
The harder problem will most likely be getting hold of the TV listing data in a usable format.
If you are lucky enough to be in a region that uses DVB-T then it might be possible to extract the 7 day listing that are broadcast over the air, otherwise look at the MythTv project as that had listings collectors for many different regions