I'm moving my company's blog out of Medium to a subdirectory of our domain name.
We have three blogs, one on a subdomain (when Medium still allowed it) and two as regular Medium organization blogs.
To my knowledge, Medium doesn't let you set redirects or edit canonical URLs after a blog has been published which means that there is no technical way to indicate to search engines that the content moved.
My plan is currently to migrate the content to our new blog but set canonical URLs that point back to their original Medium URL so as to not have an empty blog, duplicate content or lose backlinks to our original blog.
I've thought about it for a while but just wanted to make sure that this is my best option since this will mean that our new blog wouldn't rank on old content.