It’s a fairly safe bet your original post in this thread was not speakig of sim coding...
Any modern US aicraft, minus the A-10, is going to be uncontrollable without hydro as all the actuators require it. That goes for the 18, 15, 16...the list goes on. As long as the engines are spinning and driving the AMADs, there can still be hydo pressure...and that doesn’t mean the engines have to be “on” either.
As far as what DCS models in terms of mechanical functionality...you’ll have to take that up with them.