A demo for the Switch port of the last 3DS Monster Hunter title is available on the Japanese eShop, available for all to test in docked and handheld modes.
The Switch isn’t region-locked, so all western Switch owners have to do is make a free Japanese account on the system and use that account to go into the eShop. If you are worried about getting Japanese news announcements on your Switch that you can’t read, go to Settings, System, News Channel, and then unsubscribe from everything in Japanese, including the few channels that are both Japanese and English.
Capcom has not changed their stance on the localization of Monster Hunter XX, meaning this might be the easiest modern way for western players to take handheld Monster Hunter for a spin. The game is scheduled for release in Japan on August 25. Monster Hunter World is expected in early 2018 for PlayStation 4, Xbox One, and PC.