FediHood is a social network built around the place where you live. You choose a city and the topics you care about, then read what neighbours are saying and join in.
It stays a normal fediverse app. Your posts can reach Mastodon, PixelFed, Misskey and the rest, and posts from those servers reach you too.
Source code: https://git.holos.social/tom79/FediHood
There’s only one instance so far: https://fedihood.social/
If new instances are created, they should show up here: https://fedihood.fediverse.observer/list
I don’t think an encrypted message feature is necessary for this kind of a web app. If people want to send encrypted messages, they can just switch to a different service for that. Like you get them to know on fedihood, exchange matrix handles or phone numbers or whatever, and then you can use a different service for private communication.