Adicionar opções do produto aos produtos do loop

functions.php

<?php
/*
 * @version 1.1.0
*/
add_action( 'woocommerce_after_shop_loop_item_title', 'lpb_wc_add_product_options', 9 );
function lpb_wc_add_product_options () {
	global $post;
	$product = wc_get_product( $post->ID );
	if ( ! $product->is_type( 'variable' ) ) return;
	
	$get_variations = sizeof( $product->get_children() ) <= apply_filters( 'woocommerce_ajax_variation_threshold', 30, $product );
	$available_variations = $get_variations ? $product->get_available_variations() : false;
	if ( $available_variations === false ) return;

	$attributes = $product->get_variation_attributes();
	$selected_attributes = $product->get_variation_default_attributes();

	foreach ( $attributes as $attribute_name => $options ) {
		if ( empty( $options ) || ! taxonomy_exists( $attribute_name )  ) continue;

		echo '<div class="product-attribute product-attribute-' . esc_attr( $attribute_name ) . '">';
		echo '<ul class="attribute-options">';

		$terms = wc_get_product_terms( $product->id, $attribute_name, array( 'fields' => 'all' ) );

		foreach ( $terms as $term ) {
			if ( in_array( $term->slug, $options ) ) {
				echo '<li class="attribute-option attribute-option-' . esc_attr( $term->slug ) . '">';
				echo '<span class="label">' . esc_html( apply_filters( 'woocommerce_variation_option_name',  $term->name ) ) . '</span>';
				echo '</li>';
			}
		}

		echo '</ul>';
		echo '</div>';
	}
}

style.css

.product-attribute .attribute-options {
  list-style: none;
  padding: 0;
  margin: 0;
}

.product-attribute .attribute-option {
  display: inline-block;
  margin: 0 0.25em;
  padding: 0.2em;
  border: 1px solid #ddd;
}

/* não mostrar o nome da opção */
.product-attribute .label {
  display: none;
}

/* 
  Aqui um exemplo de criar "amostras de cores" do produto.
*/
.product-attribute .attribute-option::before {
  content: '';
  display: block;
  box-sizing: border-box;
  width: 1em;
  height: 1em;
  background: #ddd;
}

.product-attribute .attribute-option-black::before {
  background: #202020;
}

.product-attribute .attribute-option-blue::before {
  background: #5D8DB3;
}

.product-attribute .attribute-option-green::before {
  background: #718464;
}