Two completely different things by nature. What you do with shader2rbg and how you use the result maybe can become a toon shader, I’ve never tried as I’m not into toons or Eevee. I’ve only tried using it for completely different things that cannot be achieved outside Eevee or using other techniques.
But I guess you could quantify the output using a ramp on glossy and diffuse shader to make it look toon’ish. Never tried it though.