The DLC is paid (around $5.99 USD) and can be purchased via the Nintendo eShop or Steam store. There is no 鈥淣SP2鈥� or 鈥淩OMiozip exclusive鈥� DLC.
Install Atmosphere:
Yes 鈥� but only one official DLC.
In June 2021, Cranky Watermelon released the 鈥淏oomerang Fu 鈥� Rising DLC鈥� for Nintendo Switch, Steam, and other platforms. dlc boomerang fu nsp2 dlcsswitchromiozip exclusive