Use an Eel-Expression in PHP

EelEvaluator

/** @var Site $site */
$site = $this->siteRepository->findOnline()->getFirst();

/** @var ContentContext $context */
$context = $this->contentContextFactory->create(array("currentSite" => $site));

$eelEvaluator = $this->objectManager->get('TYPO3\Eel\EelEvaluatorInterface');

$result = \TYPO3\Eel\Utility::evaluateEelExpression('${q(site).find("myQuery").get()}', $eelEvauator, array("site" => $context->getCurrentSiteNode()));