Translate labels and descriptions without i18n_field

mymodule.php

<?php

/**
 * Implements hook_field_attach_view_alter().
 */
function MYMODULE_field_attach_view_alter(&$output, $context) {
  foreach (element_children($output) as $field_name) {
    $element = &$output[$field_name];
    if (!empty($element['#entity_type']) && !empty($element['#field_name']) && !empty($element['#bundle'])) {
      $instance = field_info_instance($element['#entity_type'], $element['#field_name'], $element['#bundle']);

      // Translate field title if set
      if (!empty($instance['label'])) {
        $element['#title'] = t($element['#title']);
      }

      // Translate field description if set
      if (!empty($instance['description'])) {
        $element['#description'] = t($element['#description']);
      }
    }
  }
}