This is not an extension point, so adding new items to choose from to sort upon is not something you can do by configuration. If you have specific fields/properties you wish to have as options to choose in the sort, I'd suggest adding them in a new GitHub issue. Once there is an issue, someone can work on it to add it to a future release.

Add a New Issue: https://github.com/Hotcak...commerce-core/issues

Open Issues Related to Sort: https://github.com/Hotcak...issue+is%3Aopen+sort