Sorry for the harsh reply but it is really not helpful at all when you simply forward a couple of links and don’t waste a minute trying to understand my problem..
I’ve read the links, and despite being somehow related, none solves or addresses the problem. I need to change the original string from the theme, forget WPML it has nothing to do with it (my mistake even mentioning it).
I need to simply change the original strings from your theme! Both “Adresses” on the side menu, and “BILLING ADDRESS” in the detailed panel, as shown in the image!
Can you help me find where to change that?