At a glance, Misskey and associated forks may appear to be Twitter-clones, but dig a little more and you'll find they're a lot more, for better and worse.
The interface is highly customizable, not just with some different colored themes nor a multi-column interface, but that you can stack page elements in columns and set up "antennae" or filters to surface posts including specified keywords and/or hashtags while excluding others via keywords/hashtags as well. There's also what they call "channels" which I think are sort of like groups or dedicated topics apart from hashtags to post to and discuss whatever the channel topic is.
Oh, and because it seems *key wants to have a little of everything, there's Pages, which is basically longform blog posting, and some versions include simple games. There's also options for some other widgets I've not mentioned here. It's genuinely pretty wild compared to the other federated microblogging services with how much flexibility it has and all that it has packed in.
I think the only other federated service I've found that's comparable in flexibility may be Hubzilla, albeit I got the impression it's less user friendly, but still, very customizable and a lot you could do with it.