@drwho Federation features will most likely be released in Gitea 1.18, so you only have to wait until October...
You *could* try the code (https://gitea.com/Ta180m/gitea/src/branch/feature-go-ap-inbox-outbox) now, but it's all highly experimental and might cause damage to your Gitea database, so I wouldn't recommend it.
@ta180m That's good to know - thanks.