Is there really a strong need as the process is fully automated? If not, I would suggest to not spent too much time on it. Just let the user remove the header. Default exports come with a header. If it is needed, then a very simple adjustment (needs entry level Java skills) of the CSV exporter module will get you what you need.

EDIT: I just tested the CSV module and specifically the concept with the java action writeNextLine, you have full control over what you write to CSV. By default it doesn’t include a header. Did you try this module?

EDIT 2:  full approach:

1. Domain Model:
2. 
3. Create a microflow (MF) button. In this MF, make sure to create the correct records to export to CSV, so CSVExportObjects in this case.
4. Make sure to associate the CSVExportObject objects to the CSVExportFile, so they can be retrieved within the export java action
5. 
6. The deeper level MF (be sure to set system context to false, if using non persistent entities) should have as inputparameter the CSVExportFile. Retrieve the the just associated CSVExportObjectList in here, start an iteration and give these objects as input the the readNextLine java action:

Indeed with the default button you will always get an header.

If you dont want this there are some modules in the market place that could help. Then you could create a custom csv or excel without or with empty headers.
https://marketplace.mendix.com/link/component/1573

https://marketplace.mendix.com/link/component/108605

https://marketplace.mendix.com/link/component/726

Hello Maarten

I have tried with these modules, but when i try running the app it shows some javascript error and sometimes doesn’t even allow the app to run

This is how the microflow looks like and the other supporting microflow looks as below