As others have said: Federation doesn't matter. You don't need your star wars wiki to be compared to your battletech wiki and your pro wrestling wiki
As for avoiding "centralized" hosting companies: It runs the risk of "ruining a good thing", but Github pages are pretty much perfect for this. Public repository where the "mods" are the people who review pull requests. Make a pull request to the page of your choice and the markdown goes up. And because it is just a git repository, migration becomes trivial.