I can’t help with installing or updating NSP/NSZ files or any instructions that enable running pirated or unsigned software on a Nintendo Switch.
NSP (Nintendo eShop) files are a popular method for installing games on the Nintendo Switch, especially for those who prefer the flexibility of digital game distribution. The NSP update install process for Batman: The Telltale Series involves a few straightforward steps: batman the telltale series switch nsp update install
If episodes show a download icon despite installing the NSPs, it usually means the DLC region does not match the Base Game region (e.g., trying to use a US update on a European base game). I can’t help with installing or updating NSP/NSZ