The Color Mix effect strip mixes two strips by working on the individual and corresponding pixels of the two input strips.
This effect can do the exact same operation as the Add, Subtract, or Multiply effect strips but also other color blending modes.
The Blend modes can be selected in the select menu. See Color Blend Modes for details on each blending mode.
Add, Subtract, Multiply, Screen, Divide, Difference, Darken, Lighten, Overlay, Color Dodge, Color Burn, Hue, Saturation, Value, Color, Soft Light, Linear Light
The amount of the blend of the second image gets composed onto the first.