This is the most obvious danger. Downloading and playing NSP files for games you do not own is copyright infringement. Nintendo is famously aggressive in its legal pursuits.
You can find many public channels by using the global search bar in the Telegram app and looking for terms like "Switch Stuff" or "NX Resources". switch nsp telegram
Don't just use bots; join groups . In groups, users post "Request" threads. If a bot doesn't have a rare indie game, a user will upload it from their personal stash. The Complete Guide to Switch NSP Telegram Channels: