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The problem is that we have unique translations IDs in the already imported content (products) and we are doing everything by the docs to import the EN content to the website (EN is secondary) but the translations are not connecting the the original content. We verified EN and BG both have the correct and matching "translation ID"
We tested a lot of methods but we found the following:
Setting the Translation Unique Identifier by updating Product categories correctly sets the TRID with the desired value. Notice on "updating" not deleting and reuploading the categories in the original language.
After that uploading the secondary language categories with the same TRIDs works and the are correctly connected.
This approach does not however work for products.
We managed to update products and set this TRIDs to their post IDs. However when doing the secondary import for the secondary language by the docs the field we use is the same as the first import with the same values, however in the secondary language import does not set the correct TRID.
We made a small plugin that forces an attribute which holds the real TRID value and applies it to secondary language TRID.
This worked, however we are trying to report an issue for a couple of hours already.
Setting the field in WP All Import settings does not set the actual value for some reason, it generated now TRIDs which in turn does not connect the posts.
Please make a deeper dive into testing this as a fairly small workaround can fix the issue - force TRID during import, however this is not an option during the import.
