Translating custom emails

Hi, I have a site with motopress booking and woocommerce. In both plugins there are mails that are sent to the customer after making a reservation, reservation being confirmed or buying a gift card.
I know there are none of this mails in the string translation, and they’re using special tags to display prices, objects etc.
So is there any php function to check what language is displaying right now, or maybe do you have some other ideas how can I do it? I can’t get user language, since clients aren’t users.