Bumping for you, I have the same issue.
I have a repeater field “slides” which has image fields. If I set slides to copy it creates the fields but doesn’t copy over the image field data. Not unless I set each image field to copy, not ideal when setting up for a client.
I’ve put a ticket in with wpml, gave them access to my dev site but haven’t heard back yet.
In my case I’ve resorted to using the gallery custom field, but that’s no good for repeaters that aren’t images.
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