where is the transmission dip stick for 2012 xc90

There probably isn't one , Do more research or look in the owners manual and always go with the proper fluid from the dealer

More and more vehicles are filled through the transmission pan. The drain plug will have a fill plug built into it. It might have a fill plug on the side that the fluid will trickle out when full. Try googling the question.

In the front of the engine, behind the radiator fan, there's a yellow dipstick that's hard to see, you might have to move a hose to get to it. It pulls out so you can check fluid level/condition.