There's also the Nautilus "Luxury Yacht Submarine" from U-Boat Worx [1].
I don't think either of them have ever been built, they're basically just Kickstarters for ultra-rich people.
Edit: There's a link for Migaloo NFTs on OpenSea in the footer and a fanciful floating habitat that looks like a seasteaders wet dream. This does not look like a serious project. The entire site is nothing but renderings. U-Boat Worx at least ships the NEMO submersible so they kinda know what they're doing.