In a newly published Witcher 3 Switch interview, Piotr Chrzanowski, a senior producer at CD Projekt Red, confirmed that the entire game and expansions is set to be contained on the Switch game card.
Explaining how the game was ported to Switch, Chrzanowski told VGC:
“We made a lot of changes. We had to optimise the game for both the GPU, the CPU, the memory constraints… there was a lot to deal with. A lot of the changes we made are under the hood, because they’re things we had to adjust to the limitations of the hardware.”