Issue #2143023 by FrancescoQ: Move Translation tab on node translation form to right sidebar.

core/modules/node/lib/Drupal/node/NodeTranslationController.php

@@ -24,13 +24,14 @@ class NodeTranslationController extends ContentTranslationController {
     // Move the translation fieldset to a vertical tab.
     if (isset($form['content_translation'])) {
       $form['content_translation'] += array(
-        '#group' => 'additional_settings',
-        '#weight' => 100,
+        '#group' => 'advanced',
         '#attributes' => array(
           'class' => array('node-translation-options'),
         ),
       );
 
+      $form['content_translation']['#weight'] = 100;
+
       // We do not need to show these values on node forms: they inherit the
       // basic node property values.
       $form['content_translation']['status']['#access'] = FALSE;