Assuming taxonomy is required, the following result was found.
a.alias 'slug', 0 'term_group' FROM my_joomla_db.jos_categories a ORDER BY a.id; INSERT INTO my_wordpress_db.wp_term_taxonomy SELECT (a.id + @CountCategoriesAlreadyEntered) 'term_taxonomy_id', (a.id + @CountCategoriesAlreadyEntered) 'term_id',...