Custom transform

If you need to completely transform yourself, then you can create a transform method in the class. In this case, no library processing is called, all the responsibility of the conversion passes to your class.

class CustomTransformUserDTOArray
{
    public string $email;
    public string $username;

    public function transform($args)
    {
        $this->email = $args['login'];
        $this->username = $args['fio'];
    }
}