In order to change default sort order from ascending to descending in Magento 2, first you need to copy vendor/magento/module-catalog/view/frontend/layout/catalog_category_view.xml to app/design/frontend/{{Vender_Namespace}}/{{Theme_Name}}/Magento_Catalog/layout/catalog_category_view.xml into your theme.

Now copy below code to your new xml file.

Thats it. Enjoy Magento 2!! Enjoy Magewallet!!!

Ref: http://magento.stackexchange.com/questions/119642/magento2-default-to-sort-by-price-descending-not-ascending

Mahendra Paladiya
Mahendra is a Web Developer whose passions includes web development, technical blog writing, and database management. His passion for web development pushed him into learning how to handle different platforms like Core PHP, Magento, Prestashop, WordPress, CodeIgniter, CakePHP and Oracle.