There are two theories about the wedding ring. One is that the Egyptians believed, in spite of the left hand's flaws, wearing it there brought it closer to the heart. The other is that the Romans wore it there to ward of evil associated with the left hand.
#13 shows a picture of him using his right hand
Due to a right shoulder injury and arthritis in the right hand I now tend to do more tasks left-handed even though I am right-handed.
Einstein was not left-handed, it is just a myth.