If you choose to proceed with NSP installation—whether for backup purposes or hardware tinkering—ensure you own a legitimate copy of the game first. Respect the craft, support the artists, and keep the horror genre alive on the Switch.
If the game is freeware (released as "pay what you want"), then an NSP download from the official source is legal. If it is a paid title, downloading a pre-release NSP from a third party is considered piracy.
If "Dreamless" is an indie game developed by a small studio, downloading it for free directly impacts the developers' ability to make future games. Indie developers rely on every sale to recoup costs. While piracy is often debated for multi-billion dollar corporations, it is devastating for indie creators.
To understand the search query fully, one must understand the terminology. Users searching for are specifically looking for a file format used by the Nintendo Switch.