尝试在您的functions.php 文件或插件文件中-

add_filter( \'login_url\', \'wpse_290288_custom_login_url\', 10, 3 );
function wpse_290288_custom_login_url( $login_url, $redirect, $force_reauth ) {
    $login_page_id = 123; // ID of your custom login page
    return get_permalink( $login_page_id );
}