OK - we're at least getting closer ...
By 2013, the 3.5L was called the Cyclone, not Duratec (which was a predated model). This is the basis of the 3.5L EB engines, but I presume yours is the n/a version; by far the most common in that time frame for your application in the Edge. These engines wear very well; incredibly well, actually. Also, they run extremely clean. About the only issue they have is the cost of the internal water-pump (not oil related, so we'll ignore that for now, but something you definitely should be aware of for the future ...)
You can pretty much run about any lube out to 15k miles in that engine. Seriously. It won't matter; the engine does not care. The oiling system is very stout, and the engine does not have hot-spots, so coking of the rings or on top of the heads isn't an issue. The use factors don't seem to affect the Cyclone series either; hot or cold, hwy or city, they wear fairly consistently and steady.
For reference, I put my money where my mouth is ... and have the proof ...
Here is a UOA after I ran 12k miles on ST dino oil. Yes - Walmart's basic conventional oil at 12k miles, and everything was fine.
Then I next ran HPL for 10k miles. Notice that the wear rates were incredibly similar.
My most recent extended run in my 2018 Taurus n/a 3.5L. Typical mixed use; city and highway. To help this make sense, here is an OCI history: - at 1k miles, the oil/filter was changed with dino ST (first "break in" flush of the OEM machining remnants) - at 5k miles, the oil/filter was changed...
bobistheoilguy.com
Inexpensive dino oil and uber-premium boutique synthetic oil produced very similar wear, even at durations at/over 10k miles.
You can use just about any SN or higher rated lube in your application and it won't matter. 15k miles would be easily doable in the right circumstances. Now, I do NOT advocate for just running 15k miles without any knowledge of your specific engine. First, run 5k miles; get a UOA. Then 10k miles; get a UOA. Develop a good database and build up your OCIs. Do NOT just jump into a 15k mile OCI without knowing what's going on. You could have contamination issues (fuel, coolant, Si) and that would negate the longer runs.
But your question is basically easy to answer .... Any SN or higher rated lube would suffice for 15k miles in a healthy Cyclone engine. And when I say
any SN or better oil, I mean exactly that. You can run a syn if you choose to, but it's not going to do anything substantially different for that OCI duration. As long as you use a decent API spec'd lube, the Cyclone simply does not care and will not give appreciably different results, no matter what you use.