Drupal 8 hook_form_media_form_alter hooks that add entity ids to entity edit forms

your_module.module

<?php

/**
 * Implements hook_form_node_form_alter().
 */
function your_module_form_node_form_alter(&$form, &$form_state, $form_id) {
  $node = \Drupal::request()->attributes->get('node');
  // If it's the edit form as opposed to the add form.
  if (!empty($node)) {
    $orig_title = $node->getTitle();
    $nid = $node->id();
    $new_title = $orig_title . ' (node id: ' . $nid . ')';
    $form['#title'] = $new_title;
  }
}

/**
 * Implements hook_form_media_form_alter().
 */
function your_module_form_media_form_alter(&$form, &$form_state, $form_id) {
  $entity = \Drupal::request()->attributes->get('media');
  // If it's the edit form as opposed to the add form.
  if (!empty($entity)) {
    $orig_title = $entity->getName();
    $mid = $entity->id();
    $new_title = $orig_title . ' (media id: ' . $mid . ')';
    $form['#title'] = $new_title;
  }
}