Change COGS account on Fulfillment

The background for why I am asking the following is a bit involved, so I will cut straight to the chase:

Is it possible to edit by line the COGS account to which the fulfillment should post?

I want to be able to take one inventory item on two separate lines and upon fulfillment have the asset account affected the same across both lines, for the item is being taken out of inventory. However, I do not want both line items posting to the same COGS account.

An alternative for accomplishing the same thing is have a second inventory item, and every time that item is fulfilled I can have a user event create an inventory adjustment for the former inventory part, but it would theoretically be much simpler to just modify the COGS account by line item. From searches, etc, it seems that the COGS account shows up by line, although it seems as if that is merely a lookup field from the inventory part itself and not a field on the fulfillment itself.