The PublishPress Authors plugin does not currently provide an option to export or import the author's data or settings.

However, we use the WordPress API which means that any plugin that is able to export taxonomies, options and post metadata can also be used to backup or restore the PublishPress Authors data. This is the most flexible way to add and remove multiple authors from each post. Click here for more details on how Authors data is stored.

Please note: While copying the data please make sure to not modify the registers' keys to avoid breaking any relationship in the data.