At that point, why not just put it on Switch too…
Kirby’s Extra Epic Yarn was announced during the last Nintendo Direct as a 3DS port of the original fantastic Wii game. Though the game will lose a bit of its beauty in being shrunk for the lower resolution 3DS screen, it did make sense that Nintendo is doing it anyway- porting older games seems to be an easy way to service the 70+ million 3DS install base, and is something the company has done a fair bit over the last year.
However, the game’s product page on Nintendo’s site has thrown a wrench into this assumption. It specifically refers to the game as a New 3DS exclusive. What this means, then, is that only people who own a New Nintendo 3DS, New Nintendo 3DS XL, or New Nintendo 2DS XL, will be able to play the game. At that point, given that New 3DS forms a far smaller fraction of the larger 3DS install base, you do have to wonder why Nintendo didn’t bother putting the game on Switch as well.
Right now, this is just according to the page listing on Nintendo’s site, and that could be wrong. If there is any official confirmation, we will update you either way. Kirby’s Extra Epic Yarn launches in 2019.