I have exported the tag data. Now where's the 'Import' function?

I have a double album and the tracks from CD1 are labelled as though they were CD2 and vice versa. This is how they are set up on freedb.

I thought the easiest fix would be to export the tag data from each disc and then import the other way around.

Exporting is easy.

How do I import it?

Convert > Textfile - tag