Choose the device you want to buy for at the end of purchase.
At the end of purchase, make an scroll down option for the user with all the devices available, so he'll know and be able to check for which device he wants.
Just had some trouble with this, it could be simpler. Bought a game at oculus app for Windows, had no clue its only for rift S ( I have a quest 2 ), got my refund, tried again at oculus app for android, still the same stuff. If only it said explicitely which hardware or I could choose for which device I'm going to buy.