Any mod that does not support the Body Selector, but is a Native Override (Default Replacement) can be used by selecting the Native option.
WickedWhims comes with a set of default options which aim to match the game looks as much as possible, these are the Default options. click on any Sim and go to Wicked -> Personalization -> Body Selector Any creator is capable of adding their body mods to be selectable within the Body Selector, and any user can select anything on any Sim they want.
Body Selector is a core functionality of WickedWhims that allows users to select body parts Sims will use.