Concrete CMS add-on: Macareux CSV User Import & Export
This package enables it to export users as CSV files and import users from CSV files.
Concrete Core has a feature to export users, but you can select columns to export with this package.
This package supports Concrete CMS version 9+ only. You can use the legacy version if you're running Concrete CMS version 8.
https://github.com/MacareuxDigital/md_csv_user_import_export