"NSP" is a file format that stands for . It's the same digital format used for games, updates, and DLC distributed through the official Nintendo eShop. While you can also find the game as an "XCI" file (the format for physical game cartridges), NSPs are directly related to downloaded digital copies.
Digital Foundry called it “the weakest version by a significant margin.” Fans were furious, especially those who backed the Kickstarter for a Switch copy. bloodstained ritual of the night switch nsp link
Before searching for links, it is important to understand what you are downloading. "NSP" is a file format that stands for