It's a jigsaw puzzle. The image on the left is of vases of flowers; the image on the right is of Marilyn Monroe.
OK, so even knowing that the image on the left is of vases of flowers, I find it something of an effort to see the vases of flowers there. I can see MM easily enough, though.
The thing is, these puzzles use the same pieces. The diffusion algorithm created them so they could be reassembled in two different ways. This is obviously early days, but if improvements are made as rapidly as they were for single images, the result could be very impressive. There probably aren't many commercial applications for jigaw puzzles, but I'm sure other uses are out there awaiting discovery.
Naturally, I paid for this information by giving everyone in my daughter's household a cold.