Normally, this is a problem with your eyes (IPD), the glasses you tried, or the player, not the VR.
If you see the girls as giants, you probably have a high IPD (like me), which is the distance between your pupils. First, you need a headset that allows you to adjust the IPD via hardware, with a button to move the lenses until they fit in the center of your eyes. Almost all modern headsets include this feature.
Then you need a player with specific settings to reduce the size of people, such as Heresphere, Whirligig, or Virtual Theater. Generic players like Skybox are very bad at this, and all the free ones are too.
With this, you will see the girls at their normal size.
Feeling the girls in real size, in 3D and inches from your face, where the girls talk to you and you are the protagonist, is a new level of porn. I can no longer go back to 2D porn. If you're curious about VR, I invite you all to join the thread at
JAV VR.