Datagrab: Importing via Excel csv does not show foreign characters

EE 2.8.1. We’re uploading channel entries via an Excel csv with Datagrab. Entries are in French, Greek, Bulgarian, Spanish etc. Upload is fine but the special characters (such as Greek and Bulgarian) appear in the channel as “????” while “é, à, ö, ë” etc do not appear at all, there is only a blank space left in the field.

Anyone have a fix for this? Or possible explanation as to why it might be happening?