It is impossible to write an article about without addressing the legal implications.
If you already own the game but lost your copy, you can re-download it from the eShop using your Nintendo account. For homebrew or modding discussions (non-piracy), try communities like GBAtemp or the Switch Homebrew Discord. huntdown rom nsp update switch game full
If you have a digital-only Switch (Lite or OLED), an NSP is the only way to install a backup. It is impossible to write an article about