It could be nothing, but check out this steelbook case for Pokemon Sun/Moon. This was just posted by Nintendo of Canada and... Something seems amiss. Does that look like a 3DS card slot to you? Methinks someone may have accidentally leaked the NX cart, sort of.
Now, it might not be that. After all, there’s no indication that Sun/Moon is coming to the NX, and it’s entirely possible that this is just a really shitty case designed to (poorly) hold both Sun and Moon at the same time.
But why use logic when we can speculate blindly? I honestly think this may be the size of the NX cart. And it would make sense - you really don’t need a massive board to get 64GB+ of data on a cart anymore, and the rectangular shape does totally hearken back the the SNES halcyon days.
What do you think, TAY?