I can see that I can follow Lemmy communities from Mastodon (just tried it out with a handful of communities), but I don’t see a way to have it work the other way.
There’s a few lovely people on Mastodon that post things I’d love to see pop up in my Lemmy feed - like @Curator@mastodon.art, for example. But I can’t figure out how to follow them from here?
You cant follow hashtags, only follow the users who post them and then filter according to the hashtag on each post. That doesnt make sense for Lemmy (it only follows group actors, which are similar to user accounts).
Modelling tags as communities actually sounds like a good idea though. But you wouldn’t want to namespace them by instance, hmm. I guess they could just have their own namespace as a pseudo-instance.