Kbin is dead, Mbin is good but different to Lemmy. Also see PieFed and Sublinks.
The wonderful thing about federated services is that you can have fun with all the users on Lemmy and see all the content but not have to actually use the Lemmy software. You can even follow Lemmy communities from Mastodon and interact with posts from there (just in a Mastodon way).
Yip, Sublinks.
I’m not sure how far along they are, I don’t think I’ve seen a sublinks instance in the wild. Their demo seems to be running the Lemmy frontend still, if I’m understanding things right. But it’s basically a community project to build lemmy but in java instead of rust and they have a lot more moderation tools. It’s what Beehaw are planning to migrate to, but I think it might not be ready yet.