Thank you for very detailed answer! Respect! 😎
Edit History
first time in my carrier of talking in PrestaShop Forum I had quality anser! Unfortunatelly, my nervous level of browsing 3000 lines of that controller is too much to understand what to do to add an email.
This is final step for me to decide go out of prestashop and comeback to my natice CMS. Client is aksing again and again stupid tasks which on prestashop It takes 3-5 hours to make, and on my CMS it is 5mins.