OK, this is a strange, but amazingly wonderful thing, there's a WordPress plug-in that converts every post from a WordPress site into a Mastodon one. So now if you search for @email@example.com on Mastodon or Pixelfed, you will see the latest posts from this website.
Basically, it emulates a few cool protocols, there is webfinger which does searching for Activity Pub protocol systems. This includes Mastodon for posting and Pixelfed for pictures. There are definitely bugs where sometimes Mastodon works and sometimes it doesn't.
But the main thing is to make sure that author pages are enabled and then you should see it or search and follow. Also if you reply to a blog post on Mastodon, it appears as a comment in your blog which is pretty cool.