View Lemmy communities, user profiles, posts and comments
Follow Lemmy communities to receive new posts and comments
Replies (mentions) work in both directions, including notifications
In addition, Pleroma users can exchange private messages with Lemmy users.
Note that Pleroma and Mastodon rely on a compatibility mode in Lemmy, which means that they won’t receive events like Deletes or Votes. Other projects whose federation works similar to Pleroma/Mastodon will likely also federate.
That’s all I know. If anyone else can shed light on this, please do, because now I have the same question :P
I’m so sorry, my reading comprehension failed me. I don’t know how to answer your actual question, which is super embarrassing.
I don’t have personal experience with Friendica or Pleroma, unfortunately, but the interwebs say Pleroma users can follow Lemmy communities.
As of release v0.14.0 (we are now on v0.18):
That’s all I know. If anyone else can shed light on this, please do, because now I have the same question :P