Assuming you have a modded Switch running Atmosphere, SX OS, or ReiNX, and you own a legal copy of the base game (or a legally dumped backup), here is the standard installation process for the :
Here’s a clean, reliable breakdown for on Nintendo Switch – focusing on the NSP + Update situation. Sonic Mania Plus Switch NSP UPDATE
Use popular tools like Tinfoil, DBI, or Awoo Installer. Assuming you have a modded Switch running Atmosphere,
Sonic Mania Plus is the definitive physical and digital re-release of 2017’s Sonic Mania . It includes the base game plus all previously released DLC. The "Plus" content adds: Sonic Mania Plus Switch NSP UPDATE
English, French, German, Italian, Japanese, Korean, Simplified Chinese, Spanish, Traditional Chinese What the v1.04 Update Delivers
Improvements to load times and sprite animations. Key Features in the Latest Update