The JP N64 NSO app is objectively “better” in game library and preservation quality (unpatched ROMs). For English-only players, Sin & Punishment alone makes it worth the minor hassle.
You do not need a second subscription to use the Japanese app; your existing Switch Online + Expansion Pack membership works across all regions. nintendo 64 nintendo switch online nspjp better
If you’re using a Japanese Nintendo Account or have the JP NSP file: The JP N64 NSO app is objectively “better”
The Japanese version of the app (often identified by "NSPJP" in digital file naming conventions) is widely considered "better" by enthusiasts because it offers exclusive technical features and games that are missing from the Western version. Japanese App Advantages nintendo 64 nintendo switch online nspjp better