If you are still looking for an alternative, https://lemmy.zip/ is a solid choice. Similar moderation policy than lemm.ee.
Monthly reports: https://lemmy.zip/post/39959863
Lots of lemm.ee users moving there: https://lemmy.zip/post/40323214
If you are in the UK (where lemmy.zip is geoblocked due to UK laws), https://feddit.uk/ is a good option.
You can export your subscriptions, blocks and saves from “Settings - Import/Export settings” and then import them on your new account.
Posts are federated already, so you can’t migrate them. The content from your old account is already on the new server, just under your old account name. Importing posts to a new account, especially if they “posted” from that new account isnt possible.
It would be great to have a “migrated/archived” tab on an account that would bring over posts/content in a local only way that was just attached to that account, but that’s not a feature lemmy has.