Thanks for getting back to us, ourmaninindia.

I can see how useful for you to add the customer's name and SAC codes in the GSTR2 - 3. However, there are certain limitations for each product offered by Quickbooks.

As mentioned by my colleague, you can only add the SAC codes to your product and services. You may follow her outlined steps on how to add them.
 

We aim to find new ways to meet your needs. I'd suggest visiting the Quickbooks Blog to stay updated on any improvements in the software.

Please keep in touch if there's anything else I can do to help you succeed with QuickBooks. I've got your back.