Lots? The only one which comes to my mind is Super Mario 3D All-Stars.
Yeah. primarily a lot of their old old games that would have come out for consoles like the NES.
Quite are lot of these arent available on both digital and physical forms unless you paid silly money off ebay for one, illegally from rom websites that Nintendo are actively trying to shut down or maybe were lucky enough to find from a yard sale.
In any case, you can still find copies of 3D all-stars
same goes for activation keys. but i dont known if they are legit or not but i can find some for sale. This is what i mean by Nintendo creating an artificial shortage. They could sell digital copies but they wont, They could also make physical copies for the retail channel but they wont.