There is no oscillator inside, but the prototype of ComplexProduct has a stereo oscillator as one of its default inputs.
The ComplexProduct takes two stereo inputs: Input0 and Input1.
The left channel output is: (Input0Left * Input1Left) - (Input0Right * Input1Right)
The right channel output is: (Input0Left * Input1Right) + (Input0Right * Input1Left)
You could keep the default bottom branch which is a stereo Oscillator with Cosine on the left and Sine on the right and multiply that by your mono signal to get:
Left output : (SignalLeft * Cos) - (SIgnalRight * Sin)
RIght output: (SignalLeft * Sin) + (SignalRight * Cos)