How to specify template by tag for multiple root collections


Say I have posts tagged how-to and posts tagged faq, and both have a root url structure like: /post-slug. How would I go about specifying separate templates for these? My first instinct is to have multiple root collections filtered to tag, but Ghost doesn’t seem to work this way. I understand I can maybe use a has conditional in my template, but is there a way to specify separate templates for multiple root collections through ghost routes?

I’m developing against the ghost:3.33-alpine docker image.

Thanks for the help,
Best regards