Can you suggest what kind of pertinent info you would like to see in the person/item field? A normal bank transfer uses a Miscellaneous name in the format From Acct To Acct. I suspect that is what you might want.
However, as pointed out by @rafat and @kvvaradha, if the G/L account is listed in a supplier as an accounts payable account or in a customer as an accounts receivable account, a counterparty (person) will be added to the g/j line.
So to have the same kind of person/item as a normal bank transfer, the code would have to scan the accounts used and if they were bank accounts, set the person name. It would have to assume that credits would set the From and debits would set the To. It would have to handle the case when more than two accounts were in the g/j and if there were a mix of bank accounts and non-bank accounts.
Another possibility is to use the Quick Entry name if no other name was specified. This would be more generic because it would not be limited to bank accounts. It would be simpler to code, but still non-trivial, because the QE name would have to be added to the cart. Editing is an issue, because the QE name could be lost, because it would exist only in individual items, which could be lost if the accounts are changed.
A final thought is to create a Bank Transfer Quick Entry type, rather than using G/J. This would require a code change to the Bank Transfer page to support quick entries. This seems to make the most sense.