Проблема решена ...
/*Change text strings */
function my_text_strings( $translated_text, $text, $domain ) {
switch ( $translated_text ) {
case 'Subtotal' :
$translated_text = __( 'Your text here', 'woocommerce' );
break;
case 'Checkout' :
$translated_text = __( 'Your text here', 'woocommerce' );
break;
case 'Show Cart' :
$translated_text = __( 'Your text here', 'woocommerce' );
break;
}
return $translated_text;
}
add_filter( 'gettext', 'my_text_strings', 20, 3 );