Assuming you have a modded Switch running Atmosphere 1.5.0+ and Hekate, follow this guide for your files.
: On a legitimate Nintendo Switch, updating the game is straightforward. Simply press the "+" or "–" button on the game's icon from the HOME Menu and select "Software Update" > "Via the Internet". This option only appears for Xenoblade Chronicles 2 if your game has been updated to Ver. 1.1 or higher and you have purchased the Expansion Pass . Xenoblade Chronicles 2 Switch NSP XCI -DLC Update-
One of the biggest advantages of using the files is the ability to play the game on PC emulators, where the hardware limitations of the Switch are removed. Assuming you have a modded Switch running Atmosphere 1
Which you are using (Custom Firmware hardware or PC emulation?) Xenoblade Chronicles 2 Switch NSP XCI -DLC Update-