ot_typo3/ot_templating/Classes/Controller/OtController.php

<?php

namespace Opentalent\OtTemplating\Controller;

use TYPO3\CMS\Core\Utility\GeneralUtility;
use TYPO3\CMS\Extbase\Mvc\Controller\ActionController;

class OtController extends ActionController
{

    protected function setTemplate(string $name) {

//        if (isset($this->settings['template'])) {
//            $subdir = $this->settings['template'] . '/';
//        } else {
        $subdir = 'Classic/';
//        }

        $this->view->setTemplatePathAndFilename(
            GeneralUtility::getFileAbsFileName(
                'EXT:ot_templating/Resources/Private/Templates/Event/' . $subdir. $name . '.html'
            )
        );
    }
}