If you happen to purchase the game on PS5 and Switch 2, dev CD Projekt RED has confirmed you’ll be able to transfer your progress between the devices, meaning you’ll be able to pick up your progress wherever you please.
It should be noted that you will need to own the game on both platforms to take advantage of this; the Ultimate Edition will retail for $69.99 on the Switch 2.
This feature was also available in the original Switch’s “impossible” port of The Witcher 3: Wild Hunt, and it was pretty useful there too. Kudos to CD Projekt RED for committing to cross-save across its titles.