It was not even an option till 2014. So there would be no wring harness to plug into. You would be to get all the parts from a 2014, which are not even out yet. So, no, You can't add to your older Sorento.
I read in a review regarding the liftgate "Kia says the new chassis allowed the feature for 2014 because the previous Sorento wasn't rigid enough to support the power feature." - Cars.com
There's your answer - NO.