Welcome to the Community. It would be my pleasure to answer any questions you may have with creating inventory adjustments in QuickBooks Desktop.
The ability to make adjustments to the quantity and value of the inventory items are only available within the QuickBooks program. Right now, importing and exporting adjustments with Excel is currently unavailable.
For additional insight into adjusting inventory quantity or value, such as the available options, I'm adding the article that I recommend:
Please know I'm always available here whenever you need further assistance with inventory adjustment. You can keep in touch with the Community anytime.