For the most current NSP update and information on available DLC for Torchlight II on the Nintendo Switch, I recommend checking the Nintendo eShop listing for the game. The eShop will have the most up-to-date version of the game, which likely includes all previous updates and DLC.
: The primary DLC available on the Nintendo eShop is the Polish Language Pack , which is free to download. Torchlight II Switch NSP UPDATE DLC