Not that it is not interesting but I would like just a tad more variety on the front page.
Edit btw for those who are wondering the two communities I started are https://lemmy.world/c/newmusic and https://kbin.social/m/musicfeedback/microblog (not sure if I have the links correct for people)
Just checked, it doesn’t look like that sublemmy is federated with this one. I need to create yet another account to comment there.
That’s not how any of this works…
Communities (as you put, sublemmy) can’t be individually federated, only instances can be. And needing another account is a sign that you are looking at a post on the wrong instance, not a sign that an instance is not federated. In fact, finding out an instance is not federated can be pretty difficult unless you check the list of instances that are defederated on another instance.
That’s not a universal link, so you ended up on a different instance. A much simpler and easy explanation than what you came up with.