Groups user chooses plugin allows your new users choose to join to a group.
They can choose in the registration form and/or the woocommerce checkout page.
You can select the default groups to new users.
You can set groups by roles, so when an user is added to a role, he will be joined to the role’s groups.
[guc_select /] Display a select, where the user can change his groups from the frontend.
Enable on customer registration on the “My account” page.