UPDATE - Now we're hearing that these games ARE ports. Nvidia's Chinese site has a blurb that says the games are streaming, but now an Nvidia rep has come forward to say that information is incorrect.
Here's a little tidbit of info on yesterday's report of Nintendo's Wii/GameCube games heading to the Nvidia Shield. It turns out these games are streamed, and not a straight port that you fully download. The titles are accessed through the GeForce Now streaming service.