Theming translation links
I found a solution by myself. May be useful for others I think:

/**
 * Implements hook_node_view_alter()
 */
function MYMODULE_node_view_alter(&amp;$build) {
    if (isset($build['links']['translation'])){
        $build['links'] = array(
            'translation' =&gt; array(
                '#theme' =&gt; 'links__node__translation',
                '#links' =&gt; $build['links']['translation']['#links'],
                '#attributes' =&gt; array('id' =&gt; 'translation_links')
            )
        );
    }
}


* Now my links have their own ID, so I can customize them as I need with css
* If you need to custom only these links, I suggest to use MYTHEME_node_view_alter()