GET http://<magento_host>/rest/V1/products?

searchCriteria[sortOrders][0][field]=updated_at
searchCriteria[pageSize]=10

GET http://<magento_host>/rest/V1/products?searchCriteria[sortOrders][0][field]=updated_at&searchCriteria[pageSize]=10

MagentoCatalogApiProductRepositoryInterface::getList

use MagentoCatalogApiProductRepositoryInterface as ProductRepository;
use MagentoFrameworkApiSortOrder as SortOrder;

 /**
 * @var ProductRepository
 */
protected $productRepository;

public function __construct(
    ProductRepository $productRepository,
) {
    $this->productRepository = $productRepository;
}


public function getLatestProducts($limit)
{
    /** @var MagentoFrameworkApiSearchFilterGroup $searchCriteriaGroup */
    $searchCriteriaGroup = $objectManager->create('MagentoFrameworkApiSearchFilterGroup');
    /** @var MagentoFrameworkApiSearchCriteriaInterface $searchCriteria */

    $sortOrder = $objectManager->create('MagentoFrameworkApiSortOrder');
    $sortOrder->setField('updated_at');
    $sortOrder->setDirection(SortOrder::SORT_DESC)

    $searchCriteria = $objectManager->create('MagentoFrameworkApiSearchCriteriaInterface');
    $searchCriteria->setFilterGroups([$searchCriteriaGroup]);
    $searchCriteria->setPageSize($limit);
    $searchCriteria->setSortOrders([$sortOrder]);

    return $this->productRepository()->getList($searchCriteria)->getItems();
}