I think there might be some unaddressed confusion here. I see you mention “lemmy world”, however that is just one instance running Lemmy software. It is open-source, so maybe somebody could fork it, but I don’t think it’s something to ask from lemmy.world. Maybe from the official Lemmy devs, but do keep in mind they’re just volunteers.
As for posting on your profile, that’s something for the side of micro-blogging. Standalone, that could be Mastodon in the Fediverse. But there’s also MBin (active KBin fork) which is compatible with Mastodon.