PS.
since the CSV import overwrite anything with the same placeID thats in the database, it will not work with Alternative Place Names… It will only use the last name in you csv with a given PlaceID…
So to be able to import a csv list with multiple names for the same location, you either need to write a VBA that creates a Gramps XML or JSON…
or change to csv export/import to support adding/merging Alternative Names instead of overwriting the records already in the database…