NO engine "struggles" with anything if it's running right. It just turns RPMs and pulls.
Ecoboost engines produce "eco(nomy)" or "boost," not both at the same time.
Towing a big draggy trailer, it is going to be producing more boost, using more fuel.
To put it simply, there is no free lunch here. It takes fuel to make power.
How much towing do you really do? All day every day, then fine, upgrade to the F250 diesel. Once or twice a month, live with what you have and enjoy the fuel economy the 99.9% of the time you're not towing.