@samuel34 you have an invalid concept with a duplicate french name among the concepts you are attempting to import, please look at the error details for the uuid of concept and try to fix it before you try again.
On a second thought and may be this is a very naive question, if the server can allow the duplicate names concepts to exist why can’t the metadata sharing module simply export them? What I am wondering is, how does a server end up with duplicates if it is not supposed to be allowed in the first place? Is it possible that they are created outside the API may be or am I missing something?
You could validate the concepts on your server. It’s likely to find the same problem with duplicate names for “yes” in Portuguese (pt) and French (fr) locales. The validation module does a great job of finding duplicates, but you need to clean them up.
You have several invalid concepts on the source server, I bet if you tried to save one of those offending concepts on the source server on the concept form page in the legacy UI, the operation would fail with that exact same error.
You can use the validation module to find all invalid concepts and fix them before you import them.
I think the easiest fix for testing purposes is retiring the concept that is not being used or renaming as per Wyclif suggestion. Otherwise the comprehensive solution would be to use the validation module as per Ellen’s suggestion.