Add Mailtrap to Wordpress

functions.php

/**
 * Define CONST values in ENV file
 */

function mailtrap($phpmailer) {

  $phpmailer->isSMTP();
  $phpmailer->Host = 'smtp.mailtrap.io';
  $phpmailer->SMTPAuth = true;
  $phpmailer->Port = 2525;
  $phpmailer->Username = $USERNAMECONST;
  $phpmailer->Password = $PASSWORDCONST;

}

add_action('phpmailer_init', 'mailtrap');