Hi @MrOCW , eager mode quantization is manual as in you would have to change the modeling code do add quants/dequants and specify fusions.  FX graph mode quantization is automatic but it requires the model to be symbolically traceable.
Usually for new models I’d recommend trying FX graph mode quantization first.  If the model is not symbolically traceable, then you would have to either make it symbolically traceable (difficulty depends on the model), or use eager mode.
I remember looking at yolov3 a few months ago and that model was challenging to make symbolically traceable.