I haven't tried it, but Read You (A modern and elegant RSS reader with Material You design) https://f-droid.org/packages/me.ash.reader/ claims Fever compatibility.
and commafeed is in #NixOSPackages https://search.nixos.org/packages?channel=24.05&show=services.commafeed.enable&query=commafeed
So I'll put both on my to-try list. I'm tired of #Feedly and #gReader Pro, which has become difficult to install on my #GrapheneOS so that it recognizes my license.
