This utility will allow you to Export Variant Assignment information (Unplaced/Replaced) for all variants in a project. The exported VAriant info can later be imported into another project. In case the Variant exists in the target project, the import will create a new one with <_Variant_Name>. The script allows writing to xls. as well, but it will slow it down.
I cannot take credit for creating this script, I merely modified it to my and my customer's needs. I honestly cannot remember where this script came from originally.