In YT vid there was statement that freestyle works only with 900 or newer series cards. As a poor man version I use Nvidia control panel => adjust desktop color settings => tune brightness, contrast and digital vibrance. Not as nice end results but easy to try out.
I dont think its right with 900 series... i use freestyle on my laptop too...was an 850m gtx...
Yes the screen options is better then nothing...
Many people have problems with the driver i use...but there is no any issues I had on any game with... stable...doesn't matter what I play... so give it a try...
Googled it but I did not find much relevant information about freestyle HW requirements. My card is old 500 series, Nvidia doesn't even release new drivers for it. Freestyle comes with Geforce Experience application but I have no idea if functionalities are bound to certain driver version, I have no GF Experience installed at the moment because of reasons. So I have to admit that I am a bit lazy to try out.