Adam Mosseri:
Second, threads posted by me and a few members of the Threads team will be available on other fediverse platforms like Mastodon starting this week. This test is a small but meaningful step towards making Threads interoperable with other apps using ActivityPub — we’re committed to doing this so that people can find community and engage with the content most relevant to them, no matter what app they use.
fairly easy. you can export the list of your followers and followed account, block lists, bookmarks and so on, and import them in the new account. the posts you’ve made aren’t moved, though. https://fedi.tips/transferring-your-mastodon-account-to-another-server/
Thanks
That’s kind of a fail, and a feature that could be added (with some work).