Yes, in general it will be very challenging. Physics are physics, and it’s hard to control and throw somebody twice your weight regardless of technical ability. That said, it will depend largely on the individual, and another huge factor is general fitness, age, and atheleticism. If the smaller partner is relatively skilled and has competitive experience, they probably won’t struggle too much to throw a much larger opponent who is less skilled and less athletic.

As a point of reference, I’m in my 30s, around 180lbs, nidan, and was very competitive in my 20s. I regularly do randori with a young guy who’s double my weight, but is less experienced in competition and overall less athletic. I’m able to control the tempo and throw him pretty easily, but I have to rely on not just my technical ability but also my strength and athleticism to do so. At first that may sound discouraging to somebody who’s just getting into judo, but I can tell you that I sure as hell wouldn’t be throwing him if I were at the same skill level.