missed one ...

src/User/Controller/AdminController.php

@@ -128,6 +128,7 @@ class AdminController extends Controller
             [
                 'dataProvider' => $dataProvider,
                 'searchModel' => $searchModel,
+                'module' => $this->module
             ]
         );
     }

src/User/resources/views/admin/index.php

@@ -24,7 +24,6 @@ use yii\widgets\Pjax;
 $this->title = Yii::t('usuario', 'Manage users');
 $this->params['breadcrumbs'][] = $this->title;
 
-$module = Yii::$app->getModule('user');
 ?>
 
 <?php $this->beginContent($module->viewPath . '/shared/admin_layout.php') ?>