write.as is a blogging service that's currently adding (optional) federation support. This could make an interesting compromise as its designed to handle longform content but is primarily federating with shortform/microblogging style platforms (mastodon and pleroma are both primarily shortform - aka character limits, no formatting besides returns - though i understand the character limit on the latter is quite high, pixelfed is image or video + a short caption, peertube is video and title metadata only)
We'll see how that works out, I suppose