Mark sales invoice as expense

Hello, we are selling a bunch of items to customers, I made divisions to later know profit/loss … but certain items are send to the customer that should be counted as our expense.

I tried creating a sales invoice to the customer, choosing division then adding another row to subtract the total money and put it in the expense. which works fine, but I don’t want it to appear in the customers report. but still affect the division.

It’s like selling it to myself… move cost of goods into expenses while reducing inventory amount. and still being able to choose a division

what is the correct way to approach this?

Sorry, inventory write-offs was I was looking for