wpmem_email_shortcodes

// Default email shortcodes for user emails:

$shortcodes = array(
    'blogname'     => $arr['blogname'],
    'username'     => $arr['user_login'],
    'password'     => $password,
    'email'        => $arr['user_email'],
    'reglink'      => $arr['reg_link'],
    'members-area' => $arr['wpmem_msurl'],
    'user-profile' => $arr['wpmem_msurl'],
    'exp-type'     => $arr['exp_type'],
    'exp-data'     => $arr['exp_date'],
    'exp-date'     => $arr['exp_date'],
    'login'        => $arr['wpmem_login'],
    'register'     => $arr['wpmem_reg'],
);

/*
 * In addition to the above, any meta keys for fields 
 * in the WP-Members fields tab are included as shortcodes.
 * For example, if you have a field with a meta_key
 * of "my_special_field" there will be a shortcode for
 * [my_special_field]
 */
 
// Default email shortcodes for admin notification email:

$shortcodes = array(
    'blogname'      => $arr['blogname'],
    'username'      => $arr['user_login'],
    'email'         => $arr['user_email'],
    'reglink'       => $arr['reg_link'],
    'exp-type'      => $arr['exp_type'],
    'exp-data'      => $arr['exp_date'],
    'exp-date'      => $arr['exp_date'],
    'user-ip'       => $arr['user_ip'],
    'activate-user' => $arr['act_link'],
    'fields'        => $field_str,
);            

/*
 * Custom fields are included in this array, 
 * the same as user emails above.
 */

add_filter( 'wpmem_email_shortcodes', function ( $shortcodes, $tag, $user_id ) {
  
  // $tag is the email that is being handled.
  // possible tags are: newreg|newmod|appmod|repass|getuser
  
  // This will add a shortcode [my-custom-value] that would be replaced with "Here Is My Value".
  $shortcodes['my-custom-value'] = "Here Is My Value";
  
  // This is an example of a shortcode replaced with a user meta field (by user ID).
  $shortcodes['my-user-field-value'] = get_user_meta( $user_id, 'my_user_field', true );
  
  return $shortcodes;
  
}, 10, 3 );