function my_variation_is_purchaseable( $is_purchaseable, $variation ) {

    if ( ! function_exists( 'wp_fusion' ) ) {
        return $is_purchaseable;
    }

    if ( wpf_user_can_access( $variation->get_id() ) ) {
        return false;
    }

    return $is_purchaseable;

}


add_filter( 'woocommerce_variation_is_purchasable', 'my_variation_is_purchasable', 10, 2 );