Depends on your skills and if you have to tooling to do the swap. It is not just engine/trans anymore. You have to get the IC, wire harness, ECU, BCM and any other modules that would need to "talk" to the ECU to make it work. ABS/TC/SC ect all have to be considered.
Still think it is cheaper to trade in and go to and ST than trying this swap. The cost of the swap and constant issues it will cause are not worth the upgrade. ST's are cheap and companies like Cobb racing can make an ST powerful and a joy to drive. Hope this helps.
Yes, to do this swap, you would have to basically do an RS swap. Wiring from front to back and all modules. You would have to change the dash, center console, both front seats because all wiring was different from 2012-2014 then 2015-2018. I did a 2014 Titanium swap to a 2016 Titanium and i had to change everything in the car. Well except the carpeting and the headliner. But i had to get a different headliner wiring harness. I can tell you from my experience, i would never do this project again. After 2012 the can bus system is very complicated to get working after you get all the modules installed. Unless they all came from the same car it's a royal pain in the but.