You can define and edit the variant/option effectivity for a single instance under a root object or mass edit it for multiple instances under the same root object using a grid.
Editing Variant/Option Effectivity Copying and Pasting Variant/Option Effectivity Highlighting Products with the Specified Variant/Option Effectivity Managing Columns to Configure Variant/Option Criteria Mass Editing Variant/Option Effectivity Edit Variant/Options Effectivity Grid