As Florent mentioned that there is no OOTB way to export the data back to FDA, but there are few options that you can implement.
Option 1: Create an extract csv file for data segment you want to export and use FTP to transfer that file to the external server and use that file to import that data into your external system.
Option 2: Look for some APIs exposed by your Data provider for bulk updates, i.e., SOAP or REST-based APIs and write a custom connector to post that data to that third party system from a technical workflow.
Option 3: Use OOTB SOAP web services exposed by Adobe campaign and consume that data in a third party system(Don't forget to check your license for API calls with Adobe)
I am trying to use the data present in PostgreSQL database (which is installed on my local machine) and adobe console is also present in my local machine so i am trying to use the data from DB but i am not able to create external account. is it possible??