I think you misunderstood. You don’t add the column and cells with “;” then upload the list, you add the column and the semicolons then highlight the cells with the value you want to add to your filter/smart list criteria/whatever, Copy them, then Paste them into Hubspot. For example, if you were creating a smart list and you only wanted to include Contacts with a Mailing Country value of Mexico, Canada, or Europe, you would create the list, select a Filter Type of Contact properties>Mailing Country, then select Is Equal to Any Of, then go to your spreadsheet and copy (Ctrl+C) the cells with the country names and the ; cells beside them and then Paste them (Ctrl+V) into the “Add Values” flled in Hubspot. The result would be this:
Then you just save your new list. This saves you all the work of either typing each individual value or copying/pasting them in one at a time. Very handy for adding a bunch of different filter values at once.