i hesitated with whether to respond or not, as the motive for the question is not very clear.

Are tou concerned about the disturbance the airplane gives to its environment or concerned about maintaining the correct course for your aircraft?

I assumed the latter in my response below:

If you are adding ballast to a 10kg aircraft to double its mass (@20kg), then you are multiplying its cruise speed by Sqrt(2)=1.414.

Now the rest is a question of vector algebra. Say, your aircraft cruises at 10m/s at 10kg without ballast and the cross-wind speed is 5m/s. Then your drift angle is atan(5/10)=26.6 degrees which means you need to point the airplane 26.6 degrees upwind to maintain your intended course.

Now, with ballast, your drift angle becomes atan(5/14.14)=19.5 degrees, which means you are able to maintain a slightly straighter course with less drift.