add_filter('angelleye_paypal_plus_shipping_line1', 'th_angelleye_paypal_plus_shipping_line1', 10, 2);

    function th_angelleye_paypal_plus_shipping_line1($shipping_address_1, $order_id) {
        $shipping_address = get_post_meta($order_id, '_shipping_address_1', true);
        if (empty($shipping_address)) {
            $house_no = get_post_meta($order_id, 'hausnummer', true);
        } else {
            $house_no = get_post_meta($order_id, 'shipping_haus_nummer', true);
        }
        if (!empty($house_no)) {
            $shipping_address_1 = th_limit_length($shipping_address_1 . ' ' . $house_no, 100);
        }
        return $shipping_address_1;
    }

    function th_limit_length($string, $limit = 127) {
        if (strlen($string) > $limit) {
            $string = substr($string, 0, $limit - 3) . '...';
        }
        return $string;
    }