[fiatjaf]

Ignoring the body of your question and answering just the title, I'm developing https://accountd.xyz/ as a system for mixing and linking identities (email, twitter, github, trello, indieauth for now) and using that for https://trackingco.de/, https://listhub.xyz/ and https://sitios.xyz/.

In theory anyone can use it, it works automatically and you don't have to register or anything like that, but I don't know if people are interested in it.