Looking for this sidebar Add-on if it is one!

[oO5 Dynasty]

The You Tube Subscribe buttons in the youtube talent section. Amazing feature!

 

[Divvens]

I answered your question on your other thread. Did you have a look at the add-on linked there and did you go through the add-on details?

Looks like something the Widget Framework will be easily able to accomplish. Though on the site mentioned in your screenshot it could also be a custom template.

 

[FredC]

https://developers.google.com/youtube/youtube_subscribe_button