By default, our app syncs the discounted order total in QuickBooks but if you want discounts to be shown in the order synced to QuickBooks, then you can select 'Yes' in the 'Do you want to sync Discount as Line Item field' in the Order Settings tab.

The discount line name will be "Shopify Discount Product". Please check the below screenshot.

You can select the appropriate value while doing the setting of the app or update the settings later to sync discount as a line item.

When the discount as a line is set to Yes, our app will automatically sync discount promo codes along with the order in the QuickBooks "Description Field". Please check the screenshot below.