dns0.eu is a French non‑profit organization founded in 2022 by Romain Cointepas and Olivier Poitrey — co-founders of NextDNS.
DNS4EU is an initiative by the European Commission that aims to offer an alternative to the public DNS resolvers currently dominating the market.
Ah. I guess the functionality descriptions may not be up to speed since it's just entered testing - that's how they describe it in the e-mail I got from their newsletter (that it just entered testing). Here they say they don't apply legal filtering. So the domain the other poster mentioned could be added by mistake