The sales tax you are talking about is called "Use Tax".
So first you have to have a way to track use tax owed, google for QBO use tax there are several ways to do it.
Then just sell the item to the customer for a zero sales price, that will take care of the COGS posting.
If you include the item at a zero sales price WITH the sale of another item, use tax does not have to be computed, tracked or paid - best way to do it IMO