You're looking for information on downloading Red Dead Redemption on the Nintendo Switch for free using an NSP file.
Free Download Risks: Downloading Red Dead Redemption or any other game via NSP files from untrusted sources can pose risks to your device and personal data. These risks include:
The game is the intellectual property of Rockstar Games. Under the Digital Millennium Copyright Act (DMCA)
Downloading Red Dead Redemption as a free NSP file for the Nintendo Switch from third-party websites is illegal. Nintendo explicitly states that the only legitimate way to download their games is through the official Nintendo eShop or the Nintendo website. Nintendo Support
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The Appeal of Free or Gratis NSP Downloads
While the desire to access games for free might seem appealing, several issues arise from such actions:
Warning: I must emphasize that downloading copyrighted content for free without permission is illegal and can result in severe consequences. NSP files are a format used for Switch games, but obtaining them without purchasing the game or owning a physical copy can be considered piracy.