I know that Lemmy and Kbin can see each other's content, but what about the other 'form' of site like Mastodon or Pixelfed?

Lemmy and Kbin is more forum-like or reddit-like in its discussion form while Mastodon is more twitter-like or microblogging

While I know that Lemmy can see Kbin and vice versa, does this also extend to Mastodon and Pixelfed?

Can I see Mastodon and Pixelfed content in Lemmy/Kbin ? and the other way around as well ? (see Lemmy and Kbin content through Mastodon or Pixelfed)

I'm curious on how it works (as a layman), because on Mastodon you follow people/users not communities.