Change Password/Confirm_Password Password Tips
so I managed to tinker enough to get something to work and I'm sharing it in case other people need it or something. Of course, I dunno if this is optimal or follows standards or shouldn't even be done in the first place but please feel free to add your input. It's in the my_module.module file, by the by. Oh and don't mind the text, was just kinda testing this out and all that jazz.

Without further ado, here's the code:

/**
 * Implements hook_form_alter().
 */
function &lt;my_module&gt;_form_alter(&amp;$form, \Drupal\Core\Form\FormStateInterface $form_state, $form_id) {
  if ($form_id === &lt;my_custom_form_id&gt;) {
    // Note that this isn't actually a hook
    $form['#after_build'][] = '&lt;my_module&gt;_confirm_password_after_build';
  }
}

function client_confirm_password_after_build($element) {
  $drupal_settings = $element['pass']['#attached']['drupalSettings']['password'];

  $drupal_settings = [
    'confirmTitle'          =&gt; t('Do the passwords match?'),
    'confirmSuccess'        =&gt; t('Yeah'),
    'confirmFailure'        =&gt; t('Nope'),
    'showStrengthIndicator' =&gt; TRUE,
    'hasWeaknesses'         =&gt; t('Password Suggestions:'),
    'tooShort'              =&gt; t('Make it at least 50 characters'),
    'addLowerCase'          =&gt; t('Add 7 lowercase letters'),
    'addUpperCase'          =&gt; t('Add 8 uppercase letters'),
    'addNumbers'            =&gt; t('Add 8 numbers'),
    'addPunctuation'        =&gt; t('Add 10 punctuations'),
    'sameAsUsername'        =&gt; t(''),
    'weak' =&gt; t('Forgettable'),
    'fair' =&gt; t('Meh'),
    'good' =&gt; t('Almost'),
    'strong' =&gt; t('You got it'),
    'username' =&gt; '',
  ];

  $element['pass']['#attached']['drupalSettings']['password'] = $drupal_settings;
  return $element;
}