woocommerce-custom-variation-fields-value-display

echo '<option data-test="' . get_post_meta( $post->ID, 'color_hex', true ) . '" value="' . esc_attr( sanitize_title( $option ) ) . '" ' . selected( sanitize_title( $selected_value ), sanitize_title( $option ), false ) . '>' . esc_html( apply_filters( 'woocommerce_variation_option_name', $option ) ) . '</option>';