Manage vocabularies page to show vocabularies translation in other languages too.

ManageVocabulariesController.php

<?php

namespace Drupal\tools_ext\Controller;

use Drupal\Core\Controller\ControllerBase;
use Symfony\Component\DependencyInjection\ContainerInterface;
use Drupal\language\ConfigurableLanguageManagerInterface;
use Drupal\Core\Session\AccountProxyInterface;
use Drupal\Core\Entity\EntityRepositoryInterface;
use Drupal\Core\Entity\EntityTypeManagerInterface;
use Drupal\Core\Url;
use Drupal\Core\Link;

/**
 * Class DefaultController.
 */
class ManageVocabulariesController extends ControllerBase {

  /**
   * Drupal\language\ConfigurableLanguageManagerInterface definition.
   *
   * @var \Drupal\language\ConfigurableLanguageManagerInterface
   */
  protected $languageManager;
  
  /**
   * Drupal\Core\Session\AccountProxyInterface definition.
   *
   * @var \Drupal\Core\Session\AccountProxyInterface
   */
  protected $currentUser;
  
  /**
   * Drupal\Core\Entity\EntityRepositoryInterface definition.
   *
   * @var \Drupal\Core\Entity\EntityRepositoryInterface
   */
  protected $entityRepository;
  
  /**
   * Drupal\Core\Entity\EntityTypeManagerInterface definition.
   *
   * @var \Drupal\Core\Entity\EntityTypeManagerInterface
   */
  protected $entityTypeManager;

  /**
   * Constructs a new DefaultController object.
   */
  public function __construct(ConfigurableLanguageManagerInterface $language_manager, AccountProxyInterface $current_user, EntityRepositoryInterface $entity_repository, EntityTypeManagerInterface $entity_type_manager) {
    $this->languageManager = $language_manager;
    $this->currentUser = $current_user;
    $this->entityRepository = $entity_repository;
    $this->entityTypeManager = $entity_type_manager;
  }

  /**
   * {@inheritdoc}
   */
  public static function create(ContainerInterface $container) {
    return new static(
      $container->get('language_manager'),
      $container->get('current_user'),
      $container->get('entity.repository'),
      $container->get('entity_type.manager')
    );
  }
  
  /**
   * @return renderable array of elements
   * @throws \Drupal\Component\Plugin\Exception\InvalidPluginDefinitionException
   * @throws \Drupal\Component\Plugin\Exception\PluginNotFoundException
   */
  public function content() {
    $rows = [];
    $empty = $this->t('No vocabularies found.');
    
    $current_lang_code = $this->languageManager->getCurrentLanguage()->getId();
    $vocabularies = $this->entityTypeManager->getStorage('taxonomy_vocabulary')->loadMultiple();
  
    $header = [
      $this->t('Vocabulary name'),
      $this->t('Description'),
      $this->t('List terms')
    ];
    
    if (count($vocabularies)) {
      foreach ($vocabularies AS $vocab) {
        // vocabulary get translated
        $vocab_translated = $this->entityRepository->getTranslationFromContext($vocab, $current_lang_code);
        
        // ToDo: check current user for permissions to access current vocab.
        // then show the link
        $url = Url::fromRoute('entity.taxonomy_vocabulary.overview_form', ['taxonomy_vocabulary' => $vocab->id()]);
        $link = Link::fromTextAndUrl($this->t('List'), $url);
    
        $rows[] = [
          'data' => [
            $vocab_translated->get('name'),
            $vocab_translated->get('description'),
            $link
          ]
        ];
      }
    }
    
    $elements['vocabularies_table'] = [
      '#type' => 'table',
      '#header' => $header,
      '#rows' => $rows,
      '#empty' => $empty
    ];
    
    return $elements;
  }

}