Change hook to add_action in a plugin class

Question

<?php

namespace wp_gdpr_wc\controller;

use wp_gdpr\lib\Gdpr_Container;
use wp_gdpr_wc\lib\Gdpr_Wc_Translation;
use wp_gdpr_wc\model\Wc_Model;

class Controller_Wc {
    const REQUEST_TYPE = 3;

    /**
     * Controller_Form_Submit constructor.
     */
    public function __construct() {
        add_action( 'woocommerce_after_order_notes', array( $this, 'checkout_consent_checkbox' ) );
    }   
public function checkout_consent_checkbox( $checkout ) {
        $privacy_policy_strings = Controller_Menu_Page_Wc::get_privacy_policy_strings();

        echo '<div class="gdpr_consent_class"><h3>' . __( 'GDPR permission: ', 'wp_gdpr' ) . '</h3>';

        woocommerce_form_field( 'gdpr_consent_checkbox', array(
            'type'     => 'checkbox',
            'label'    => $privacy_policy_strings[ Controller_Menu_Page_Wc::PRIVACY_POLICY_TEXT_WOO_REQUEST ],
            'required' => true,
        ), $checkout->get_value( 'gdpr_consent_checkbox' ) );

        echo '</div>';
    }

I'd like to change the woocommerce_after_order_notes hook from the add action with another hook. This is a class from a plugin. I tried to include that file in functions.php and initialize that class in a variable, but I get an error saying Fatal error: Uncaught Error: Class 'Controller_Wc' not found in functions.php

$path = get_home_path();
require_once $path . "/wp-content/plugins/wp-gdpr-wc-addon/controller/controller-wc.php";
$clasa = new Controller_Wc();
add_action( 'woocommerce_after_order_notes', array( $clasa, 'checkout_consent_checkbox' ) );

I tried to put controller-wc.php in child theme to overwrite the original one, but this did not work as well.