Logseq communities on:

• kbin.social
• sh.itjust.works --> on kbin.social
• lemmy.ml --> on kbin.social
• a.gup.pe --> on kbin.social

Although on some of those magazine the federating of posts doesn't seem to work as it looks empty on here but there are posts on the respective instance

I have messed around with it. I'm one of those people who liked Roam so much that I paid to be a Founder. All these tools sound cool, but in practice, you really need to have a need for all that cross-linking.