Welcome to the forum, 'Qpr'.Just bought a 2019 optima 1.6 diesel sportswagon gt line would like to know real world mpg
As you have already bought the car, you will very soon discover the real-world mpg from the Optima over your typical driving profile, in the manner that you normally drive.
It's never a smart move to ask that question on a car forum as you are likely to attract responses from braggarts who will provide ridiculous numbers, unachievable to 99% of motorists in the real world. The Optima Sportswagon is quite a big, heavy car and those with the DCT produce a very relaxed drive once the process of getting the best from the transmission has been learned and mastered.
That said, with reasonably careful driving you should achieve satisfactory mpg from the car but perhaps you could return to the thread once you have had a chance to measure your fuel consumption and let readers know your average fuel consumption. The instruments may or may not be particularly accurate so brim-to-brim checks and simple arithmetic, along with your credit card or bank statement will reveal to you the truth about the car's economy.
I drive an earlier 1.7 diesel but the difference in performance and economy between that and the later 1.6 models is marginal rather than significant.
Good luck with your choice of car and I hope you enjoy the model as much as I have enjoyed mine over the last 4.5 years.