On or off, the 190 is never a CSP. CSP maintains a constant engine rpm regardless of throttle setting (within reason). That is why it's called constant speed propeller.
Again, reduce your throttle (Kommandogerät OFF) and your RPMs reduce. That is NOT CSP that is VPP.
You obviously haven't tried with Kommandogerät off..... try and you'll see I'm right (reduce or increase throttle, and RPM wont move).
I'm of course talking in game, not real.