For those looking for an NSP file, it seems like there's a download available here: "Everybody 1-2-Switch- -NSP--Update 1.0.1-.rar". Please be aware that downloading game files from third-party sources can pose risks to your device and potentially violate terms of service.
Launch the game. On the title screen, check the bottom-right corner. It should display Ver. 1.0.1 . Everybody 1-2-Switch- -NSP--Update 1.0.1-.rar
Supports up to 8 players in Joy-Con mode and up to 100 players in Smart Device mode. For those looking for an NSP file, it
Take and fulfill complex ice cream orders using your smart device. Everybody 1-2-Switch- -NSP--Update 1.0.1-.rar