I was asked if I could add a global template filter to the list pictured below, like "Tech Spec", so users can filter all templates with this custom filter.

I reviewed the settings and did not see anything related to this. I did some research and found no posts related so I thought I would reach out to the community and see if anyone knows how to do this, thanks in advance!
To view this in your instance go to Confluence > click on "Templates" at the top > and you will be in the view with global templates and the filters.
This is Confluence Cloud.