Talk about #DDFON (Decentralized, Distributed, Federated, Open, Network) (friendly name: #MycelialWeb), the latest iteration of #Libravatar is now using a federated software.
I think it has been that way after the service was transferred to a new team.
Having said that… what if #ActivityPub or at least the various platforms connected to the #Fediverse mycelium network, use Libravatar?
For this to work though, Libravatar would have to be updated with a new verification process to handle the non-email ActivityPub webfinger. (And I'm not sure if there are other stuff that has to be updated/added.)
If my memory serves me right, #Friendica and #Hubzilla are already doing this, although as a plugin the admin can toggle (but based on the email address attached to the account).