Theres a few ways you can have videos "fade."

Here are a few options I mess around with when using a *DJ Controller*


Turn Fader link "On". This is on the farther side of the interface. I don't remember exactly what it's called however, this links your channel fader to the video fade. This changes your channel faders to control the "brightness" of the video. Channel all the way up? video is a full "brightness". All the way down? Completely black. If you do this option you have no control over audio levels. So you would need to adjust volume from the gain, and not the fader.

Other option is turn cross fade link ON but change your channel outputs to "Thru". This allows you to maintain volume control for audio mixing but the crossfader now adjusts video only. this allows you do have cross fader video control and audio control with the channel faders. I personally prefer this.

Another way, which is the most "ghetto" is to create a black JPG in photoshop/paint or something and add that to master filter, change the opacity to create a fade.

Those are the three things that I can think of off the top of my head. I am sure there are other ways.