Woocommerce为每个变量添加不同的图标

In the list of products, it shows five attributes that have individual icons. Two of them have variables, for those variable I want to display other icons. How can I refer to variables to give it another icon?

I have tried to change:

if( $color = $product->get_attribute('pa_color') ){

by this:

if( $color = $product->get_variation_attributes('black') ){

But it gives: Call to undefined method WC_Product_Simple::get_variation_attributes()

The current code is:

add_action('woocommerce_order_action_wc_custom_order_action', 'display_attributes_after_product_loop_title', 15);
function display_attributes_after_product_loop_title(){
    global $product;

    $output = array(); // Initializing

    // The color ()
    if( $color = $product->get_attribute('pa_color') ){
        // Save the value in the array
        $output[] = '<img src="#">';
        $output[] = $color; 
    }
}