Coupon and/or discount on notification templates such as Vendor?

We need a clear indication when a customer uses a coupon code and the order is discounted. Primarily for Vendors to know when to adjust their billing such as during a sale when a customer uses a coupon code or not. Has anyone improved the order products detail to show discounts, coupons, etc.?

For what it's worth...

There have been past discussions about vendor related "commissions" - i.e., rather than the vendor billing the store, the store sends a payment to the vendor less a commission.
https://www.google.com/search?q=site%3Anopcommerce.com+payments+to+vendors+commissions

Maybe in your case the discount is product specific.  But it's possible that a discount could apply to the entire cart/order, so a calculation would be needed to determine the amount to each vendor-specific product.

If you’re using discounts such as Assigned to products, manufacturers or categories then nopCommerce will show the discounted price for each item in admin order view and it also show discount amount for each item.

Vendor can see the discounted price for their item in the order admin view but nopCommerce doesn’t shows the which discount/coupon code applies to vendors. This can implemented with customisation or a plugin.

Best Regards,
Faiz