You can do it if you find it more comfortable. Engine torque will lift the right side of the boat that's why motors a made with the tiller on the left side of the motor and the steering wheel too.
I sit on the right side, and steer with my left hand. The young guy I fish with sits on the left side of his boat, and steers with his right hand.
Whatever is comfortable to you!
If you are in a small boat it may be a little unstable to sit left of the tiller since the tiller is on the left of the outboard. If the boat does not lean to the left too much while sitting left of the tiller there should be no problem steering with your right hand. If you ever troll you may want to use your right hand if you are right handed for holding the rod and your left for steering.