You can now send orders as invoices to Quickbooks.
If an order has multiple versions, there will be multiple line items in Quickbooks. When you order proposals, the order will be automatically exported to Quickbooks as an invoice.
For this to work, you need to enable Quickbooks integration and select the Quickbooks item which will be used to store proposal items by going to Settings > Integrations > Quickbooks.

When integration is enabled, you will see an option to upload proposals to Quickbooks in the last step of creating a proposal.