Nick here from Shopify. ?
This is a great question, but currently not something which would be possible to do on the Shopify platform right now. Could elaborate a little bit about why you would want this, and how it would benefit you or make your life easier while selling? I could then pass this back to the payments team for future consideration on your behalf.
We would also like this option. Or an option to send invoices on certain products rather than take payment immediately, but only on certain products. I've literally just done research to consider transferring my shop from Squarespace to Shopify if this was an option but unfortunately it seems like it's not possible on Shopify either.