@MarcoV - Reviewing this post, @olysak mentions that the “AccountId” must be manually entered, it will not appear in the search results.
Export data to SalesForce - screenshot from that post:
So that would be the way to do it now.
In any case @dgudkov @olysak it would be useful that all the fields appear in the helper dialog, including Lookup fields, this way any Salesforce field can be selected.