I will take a stab at this since no one else has. I am guessing it will be very difficult due to all the electronics in this car. It is not like the old days where you really only needed to swap trans, add a pedal and maybe a few switchs and sensors. The whole car is now tied together electronically and the trans is a big part of that. I would suggest selling it and just buying the car you really want.
I would have to agree with granthr on this issue. Was involved in auto to 5 speed transplant into an E30. Not that difficult as most of the parts can be found in salvage yards. As mentioned, current models are just chock full of electronics. Finding the "used" pieces to complete this task will also be harder to find as well. Further agree, better, and much easier, to find yourself a manual model that started out that way.
It is very easy if all you have to do is sign the check, but it will have a few zeros after the first number (which may be an alarmingly high 5 or 6, or even higher!)
Not worth it imo. I've done a few (including swapping my e36), and even on those older cars, wiring can be a pain in the butt.