Replicating a Node with Replicate UI Leads to an Incorrect Hreflang Tag
As the module's page on https://www.drupal.org/project/hreflang says if it's for Drupal 8, then you should implement hook_language_switch_links_alter() or hook_page_attachments_alter() to modify the hreflang tags. If it's for Drupal 7 then use either hook_language_switch_links_alter() or hook_html_head_alter()