...
Create the keys and include the content only in English.
Create a page under here with a table with all languages.
Send the page to our Product Owner as soon as we already have what we need to implement via e-mail.
In case there are two ways:
Our Product Owner provides us with the content for the other languages, and we are responsible for including the content in Lokalize.
Or our Product Owner adds the content directly on LocalizeLokalize.