This is the technical support forum for WPML - the multilingual WordPress plugin.
This thread is resolved. Here is a description of the problem and solution.
Problem: Is it possible to copy all the translations for DE to AT at once without much effort?
Solution: Please visit this link where you will find how to batch duplicate content from default language to the secondary one: https://wpml.org/documentation/translating-your-contents/displaying-untranslated-content-on-pages-in-secondary-languages/using-content-duplication/#batch-duplicating