It appears to be in the region of EGR valve but also the water cooling on the oil filter assembly(which I have had trouble with in the past on a 2010 1.6 Fiat DobloMJ), though in my case it put oil into the radiator coolant.
The trouble is in your case it has been leaking for a while judging by the antifreeze stains.
If it was me I would clean it off as much as possible, then with engine off use a pressure tester to equal the normal coolant running pressure and inspect for leaks.
Note don't exceed recommended pressure or you may make more leaks.
On the water hoses they have plastic (quick fit ends) with rubber O rings inside, any of those could be causing the problem.
On the bottom right is the oil cooler, but there are many other sources.
This is a photo of the back of engine to give an idea of the problem locating the leak.