List all product attributes with the variation attributes

display-product-attributes.php

<?php

add_filter( 'woocommerce_get_item_data', 'wall_display_custom_item_data', 10, 2 );
function wall_display_custom_item_data( $cart_item_data, $cart_item ) {
	$product = $cart_item['data'];
	$attributes = wall_format_attributes( $product );
	
	if ( ! $attributes ) {
		return $cart_item_data;
	}

	$cart_item_data[] = array(
		'name' => __( 'Attributes', 'woocommerce' ),
		'value' => $attributes
	);
 
    return $cart_item_data;
}

// Save and Display the order item weight (everywhere)
add_action( 'woocommerce_checkout_create_order_line_item', 'wall_display_order_item_data', 20, 4 );
function wall_display_order_item_data( $item, $cart_item_key, $values, $order ) {
	$attributes = wall_format_attributes( $item->get_product() );
	if ( $attributes ) {
		$item->update_meta_data( __( 'Attributes', 'woocommerce' ), $attributes );
	}
}

function wall_format_attributes( $product ) {
	$attributes = $product->get_attributes();
	$out = '';
	foreach ( $attributes as $attribute ) {
		if ( $attribute['is_taxonomy'] ) {
            // skip variations
			if ( $attribute['is_variation'] ) {
				continue;
			}
			// backwards compatibility for attributes which are registered as taxonomies
			$product_id = $product->get_id();
			$terms = wp_get_post_terms( $product_id, $attribute['name'], 'all' );
			// get the taxonomy
			$tax = $terms[0]->taxonomy;
			// get the tax object
			$tax_object = get_taxonomy($tax);
			// get tax label
			if ( isset ($tax_object->labels->name) ) {
				$tax_label = $tax_object->labels->name;
			} elseif ( isset( $tax_object->label ) ) {
				$tax_label = $tax_object->label;
			}

			foreach ( $terms as $term ) {
				$out .= '<div>' . '<strong>' . $tax_label . '</strong>: ';
				$out .= $term->name . '</div>';
			}
		} else {
			// not a taxonomy 
			$out .= '<div>' . '<strong>' . $attribute['name'] . '</strong>: ';
			$out .= $attribute['value'] . '</div>';
		}
	}
	return $out;
}