Rewrite personalizado do WordPress

custom-rewrite-functions.php

<?php

    // ...

    function eg_add_rewrite_rules() 
    {
        global $wp_rewrite;

        $new_rules = array(
            'viagens/[^/]+/perguntas-frequentes/?$' => 'index.php?page_id=33',
            'experiencias/(.+)/?$' => 'index.php?page_id=31',
        );

        $wp_rewrite->rules = $new_rules + $wp_rewrite->rules;
    }
    add_action( 'generate_rewrite_rules', 'eg_add_rewrite_rules' );