custom-comments-controller.php

<?php

function create_custom_comments_rest_routes() {
	// Custom Comments.
	$controller = new WP_REST_Custom_Comments_Controller();
	$controller->register_routes();
}
add_action( 'rest_api_init', 'create_custom_comments_rest_routes' );

class WP_REST_Custom_Comments_Controller extends WP_REST_Comments_Controller {
	public function __construct() {
		$this->namespace = 'cookie/v1';
		$this->rest_base = 'comments';

		$this->meta = new WP_REST_Comment_Meta_Fields();
	}

	public function update_item_permissions_check( $request ) {
		// add custom logic here...
		return true;
	}
}