woocommerce-product-variation-descriptions.php

<?php
/**
 * Plugin Name: WooCommerce Variable Product Variation Descriptions
 * Description: Replaces the product short description with the descriptions of all visible and priced variations.
 * Version: 1.0
 * Author: Yaovi Ametepe
 * Released: July 4th, 2023
 */

/**
 * Replaces the product short description with the descriptions of all visible and priced variations.
 *
 * @param string $short_description The original product short description.
 * @return string The modified short description.
 */
function replace_product_short_description_with_variation( $short_description ) {
    global $product;
    
    if ( is_product() && $product->is_type( 'variable' ) && $product->has_child() ) {
        $variation_descriptions = array();

        foreach ( $product->get_available_variations() as $variation ) {
             if ( $variation['variation_is_visible'] && $variation['display_price'] !== '' ) {
                $variation_description = get_post_field( 'post_content', $variation['variation_id'] );
                $variation_descriptions[] = $variation_description;
            }
        }

        if ( ! empty( $variation_descriptions ) ) {
            $short_description = implode( '', $variation_descriptions );
        }
    }

    return $short_description;
}
add_filter( 'woocommerce_short_description', 'replace_product_short_description_with_variation' );