In an interview with Gamespot, Game Director Ion Hazzikostas has confirmed that there are no plans to sell Trader’s Tender as a standalone product in the store, but it may be included in certain bundles.
Gamespot Interview
3 weeks ago, we datamined new Trader’s Tender shop assets which were added on the Patch 10.1.5 PTR. According to
Gamespot, we learn that Blizzard may offer extra Trader’s Tender as part of certain bundles such as expansion deluxe editions or big bundles.