First of all, I think is a valid suggestion that of thinking twice, or more, before selling that kind of equipment.

Second, I think this is due to some "blur anxiety", a psychological condition which is not extraneous to me. By fearing you are not keeping the camera perfectly still, you actually move it.

In your case the problem is aggravated by the fact that it is an unusually light camera for you.

My suggestions:
Sustain the camera with the left open palm while keeping your left hand fingers on the focusing ring or diaphragm ring. The right hand only presses the shutter release. The right hand does not sustain the camera.

Practice without roll, during the day, paying attention to your movements.

Breathe, release your breath by a little bit, stop expiring, take picture.

Keeping the camera still must come from inside. A Zen exercise not a muscular one. Think "I and my subject are one". "I am the subject". Feel the union of all things: Photographer-Camera-Subject. Immerse yourself and your camera in this whole. Think about it 200 times x day. Become one with your camera. You and your camera are one. You and your camera are one...