The last poster says: “I found a roundabout way to go at it by transfering the posts to wordpress, I’ll figure it out from there :)” I would have liked more info on that, though I’m afraid there would still be a catch - I don’t use Wordpress anymore and never was a power user, so I’m not sure it would be possible on a free tier to stash an entire Facebook archive on a Wordpress page - and then what about importing it into the fediverse? There should be a guide for this somewhere.

Or you could just use a Mastodon instance with a higher limit of characters, unless you really need intricate formatting and/or more than one picture.