While an index could be defined for the price of a depreciating consumer good, no market-traded instrument could directly track such an index, because there would be only sellers and no buyers. The closest thing to people who "buy" the index are actual consumers who get some use from the product in exchange for the depreciation.
Shorting requires a lender who is happy to provide the product now and receive the same product back later, which in reality would only be agreed to with a large fee that would compensate the depreciation and wipe out the short trader's profit.
What can exist is a futures contract for a depreciating good, which is priced to account for the expected depreciation. The market would always be in backwardation, and shorting a future would effectively incur the "fee" mentioned above. This would strictly accomplish what you asked, "hedge some of the depreciation risk", which is only the unexpected part of the depreciation (fluctuation from the mean). The expected (mean) depreciation is not a pure risk and cannot be hedged away.
The only real solution for the companies you mention is to minimize inventory.
See this answer for similar cases where an index can only be traded as a futures contract, not directly, because it has predictable trends.