This thread is resolved. Here is a description of the problem and solution.
Problem: The client is using Vitrine theme and he can't find how to translate the strings from the cookies bar that is coming with the theme.
Solution: The strings need to be added from WPML > String Translation > Translate texts in admin screens
Here is the procedure for that: https://wpml.org/documentation/getting-started-guide/translating-theme-options/
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