It has been known for a while that the Nintendo Switch is region free, meaning cartridges from anywhere around the world will work for everyone. However, this did not guarantee that games downloaded through the eShop would be equally accessible.
Journalist Laura Kate Dale has reported that it is very easy to switch regions and access eShop games from all around the world.
You can access other region's Eshops easily. UK Switch. Make a NA account. No checks made. Log into eshop. Eshop shows NA games and prices.
— Laura Kate Dale (@LaurakBuzz) March 2, 2017
She also says that the same payment method works across regions (so your payment card wont be refused).
Some gamers have been irked in the past by Nintendo staggering online releases drastically across locations, and this could be a great solution to that. Also, there are heaps of small Japanese games that never get localised that you should now be able to play!