Downloading NSP files for games you do not officially own via the Nintendo eShop is considered piracy [5.5].
These files require a jailbroken Switch running custom firmware (like Atmosphere) and tools like Goldleaf or Tinfoil to install them onto the system or SD card [5.4]. ⚠️ Essential Warnings & Legalities RECALL Switch NSP (eShop)
The only legal and safe way to obtain this game is through the official Nintendo eShop on your Switch console. To help you further, could you clarify: Downloading NSP files for games you do not