Unfortunately, in the standard functionality, there is no option to automatically populate descriptions on those VAT settlement lines in the general journal. The entries are posted to the general ledger without descriptive text unless it is manually entered or customized.
A lightweight customization can be implemented as per your requirement to auto-fill the Description field with details such as the settlement period or VAT posting group, to meet audit or legal requirements.
If description detail is a legal requirement in your jurisdiction, a customization may be the most reliable approach.
Hope this will help you!
Regards,
Mansi Soni