I'm glad you're interested in QuickBooks Online, mpb2
Yes, there’s a workaround to allocate your production expenses to COGS, and to decrease the amount of product A once it’s turned into product B. Here’s how:
- You can create items for the production expenses, and assign COGS as their Income Account.
- Create a bundle item composed of Item A and the production expense items. This will be your Item B. (Optional) You may not put items into the bundle since you can just add them on your sales transactions.
- When you sell Item B, you’ll need to add another line for the items you’ve created for production expenses (manually enter the expense amount on the sales transaction).
Please note that the bundle feature is only available in QuickBooks Online Plus version.
Let me know if you need anything else.