Hmm, I see "Oil Temperature" / "Torque" / "Boost" ... but isn't that the engine oil temperature?
I don't know if it's engine oil or transmission oil temperature. My Kia techs at the dealership didn't know either. It's not in the owner's manual.
As I posted elsewhere, if you have an engine coolant temperature gauge, what is the purpose of an engine oil temperature gauge? They are so closely related that it would be redundant information. Transmission oil, on the other hand, although cooled by engine coolant in this car, can get very hot with repeated launches, which is one of the downsides of a torque converter transmission as compared to other launch control vehicles using twin clutch transmissions. So from a logic standpoint, I'm guessing that the "Oil Temperature" is the transmission oil temperature. Also, the engine coolant reaches a stable temperature in a couple of minutes of driving, while the "Oil Temperature" does not reach a stable 200?F until 5-6 miles of driving or longer. That suggests (but does not prove) that it's transmission oil.
Pending an answer from another Kia source, another way to find out would be to monitor engine coolant temperature while doing some launches and see if the "Oil Temperature" climbs when the engine coolant does not. The source of heat in an automatic transmission is the friction between the oil and torque converter impeller blades, so using the launch control or power-braking will heat the oil up very quickly. Hard use and launching shouldn't raise engine temperature all that much, but it will push transmission temperatures.