Summary
The Chargeback Management feature (supported on selected gateways) is used to track/settle disputes raised by end customers automatically.
You might want to export a list of transactions that were refunded to customers as part of the Chargebacks.
Solution
This can be done by navigating to Logs->Transactions-> set the filter as Payment Method is Chargeback
This will give you the list of all transactions that are chargebacks.
Related Documentation