The wpcrm_system_gdpr_export_cols_{export-type} filter functions exactly the same way as wpcrm_system_export_csv_cols_{export-type}. However, the wpcrm_system_gdpr_export_cols_{export-type} filter is only used on the GDPR export. This allows you to filter the columns that are included in the export to your contacts.

The export-type is only wpcrm-contact for the time being, unless we add additional exportable content to the GDPR page.