[jatrax]

So, for the sake of example... 50mm gives you FOV of a 75mm lens on a FF camera but the focal length is still 50?

Yes, focal length is focal length you cannot change it. The only thing that changes is that on APS-C you are cropping out a portion of the available image from the center as shown in the image above. This has the effect of looking similar to what a 75mm lens would look like on FF but it does not change the focal length.