Fedora repos are neither the RHEL repos, not the EPEL repos nor SOGO's repos. Until it is all the way to in the OS or supported by the makers, it's not supported yet. Tons of things are RPM'd by third parties for things. But none that I would use in production.
Only if you pay for Google Apps. They used to have a free tier along with Outlook/Hotmail. But the only free custom domain one now (that I know of) is Zoho.