Add custom links for specific domain

Hello,

I need to add custom links for each domain. To optimize the sitemap, I want to add specific terms for each domain. For this, I tried to add these new links with the module_simple_sitemap_links_alter() function. Here is my code:

function mymodule_simple_sitemap_links_alter(array &$links, $sitemap_variant) {

  // Create new arrays to store custom links.
  $links_custom = array();

  // Add custom variables depending from the domain.
  // Get current domain.
  $domain_service = \Drupal::service('domain.negotiator');
  $domain_current = $domain_service->getActiveDomain();
  $domain_current_id = $domain_current->id();
  $domain_current_hostname = $domain_current->getHostname();

  // Code to get specific terms with the current domain.
  ..........
   $tids = 152,5625,45;...

  $aliasManager = \Drupal::service('path.alias_manager');
  $terms = \Drupal\taxonomy\Entity\Term::loadMultiple($tids);
  foreach ($terms_root as $key => $term) {
    $links_ranges[$key]['langcode'] = 'fr';
    $links_ranges[$key]['priority'] = 0.5;
    $links_ranges[$key]['changefreq'] = 'daily';
    $links_ranges[$key]['meta']['path'] = 'taxonomy/term/' . $term->tid->value;
    $links_ranges[$key]['meta']['entity_info']['entity_type'] = 'taxonomy_term';
    $links_ranges[$key]['meta']['entity_info']['tid'] = $term->tid->value;
    $links_ranges[$key]['url'] = 'https://' . $domain_current_hostname . $aliasManager->getAliasByPath('/taxonomy/term/'.$term->tid->value);
  }

  // Merge all the links.
  $links = array_merge($links, $links_ranges);

  .....

The custom links are generated and added to the links array.

But, new links are added to all sitemaps, not just in the sitemap of the current domain.

Is is the good method to add links from custom code for specific domain? Have I omitted anything in this function? How can I proceed to create custom links by domain?

Thanks for your help.