Basically your post is already “posted” there. Anyone with a mastodon account on an instance that federates can see it. They could either paste on their mastodon search interface the url to this post and see it appear as a mastodon message. They could then reply on mastodon and it would show for you here on your lemmy instance.

They could also follow your account on mastodon or a community just as if you were a mastodon user and then see your posts on their timeline.

Not quite. Lemmy isn’t set up to make microblog posts, but mastodon users can still see community posts and comments and reply.

If some user follows you or community it will get federated into mastodon. Otherwise you can’t relly push the post into mastodon.

If a mastodon user comments on AA Lemmy post, and a Lemmy user replies, it will be delivered to the mastodon user. I’ve not tried posting to a mastodon user directly though.

Paging myself at @baronvonj@mas.to to see if this works.

Yes, but no.

@pineapplelover @tezoatlipoca You just did! It’s ActivityPub all the way down.

If you mention a Lemmy community in a post on Mastodon, it appears as a post in that community. Like this post on Mastodon: it also shows up in the Lemmy community “Linux”, and many if the comments are from Lemmy users: https://social.edu.nl/@foxy/111937325118529631

I don’t think you can do microblogging like on mbin, but I think you can directly write and reply to Mastodon users, and posts with hashtags should also be able to be found by Mastodon users if they look for them. I don’t think Lemmy threads have a hashtag field like mbin either though, so you would have to manually type them out when making a new thread.

@pineapplelover I think you just did, he says from mastodon

@pineapplelover [Waving hello from mastodon]