What is the legality of using photos in Adobe Stock in games designed for sale, via either standard license or extended license?
It would depend on how the image is used in the game. If it for decorative use such as on the box (print run less than 500K) then likely a standard issue is sufficient. If however it is part of the game itself such as a game piece or card or part of the board then it is likely the extended license is required. Please be sure to review the license agreements for specific details on allowable use.
Moving to Adobe Stock
Let me know if that helps!