You will not be able to change the transaction type of an e-way bill. The e-way bill is generated using the IRN of the e-invoice and the transaction type of the e-way bill is based on the addresses present in the e-invoice i.e., the address type of your organisation (bill-from and dispatch-from addresses) and your customer (bill-to and ship-to addresses).
Ensure that you choose the right addresses while creating an e-invoice to get the correct transaction type for the e-way bill.
You can cancel the e-way bill from Zoho Books or from the e-way bill website. Next, you need to cancel the e-invoice and create a new e-invoice with the correct address details, and push it to the IRP. Now, when you create an e-way bill for an e-invoice, the correct transaction type for the e-way bill will be generated.
Note: You can cancel an e-way bill within 24 hours from the time of creation and generate a new one.
and GST filing.