Write.as in Free version
So in that version I can post in markdown my post. I've limited option but looks enought to start.
My first feedback is that editor has no preview (or I've not found it). And you have to host yourself your image which is no very great for micro-blogging (NOTE : it is available for PRO users : snap.as)
Good thing is that you can edit a post without any problem which is not the case for other Fediverse software.
My account is well federated : @valvin@write.as
Now I'll test comments from Mastodon with this post.