AIFW - Will create categories if not found.

aifw-create-categories.php

<?php
/**
 * Plugin Name:       AIFW Create Categories
 * Description:       Will create categories if not found.
 * Version:           1.0.0
 * Author:            Mário Valney
 * Author URI:        https://mariovalney.com
 * Text Domain:       aifw-create-categories
 *
 * @link https://github.com/mariovalney/api-improver-for-woocommerce
 */

add_filter( 'aifw_api_v3_products_term_not_found', 'aifwcc_create_category_if_term_not_found', 10, 1 );                   

/**
 * Add a category when AIFW is not able to find a term by name/slug.
 *
 * Return a empty value to ignore or a valid ID to be added to Product.
 * You can use it to create a term and return it ID, for example.
 *
 * @param integer $term_id  The category/tag ID.
 * @param array   $params   The category/tag object.
 * @param string  $taxonomy The taxonomy (product_cat|product_tag).
 */
function aifwcc_create_category_if_term_not_found( $term_id, $params, $taxonomy ) {
    if ( $taxonomy !== 'product_cat' ) {
        return $term_id;
    }

    $name = $params['name'] ?? $params['slug'];
    
    $options = [];
    if ( ! empty( $params['slug'] ) ) {
        $options['slug'] = $params['slug'];
    }

    $term = wp_insert_term( $name, 'product_cat', $options );
    if ( is_wp_error( $term ) || empty( $term['term_id'] ) ) {
        return $term_id;
    }

    return $term['term_id'];
}