The tire has no inside and outside while off the wheel. Once mounted on the wheel it has an outside and an inside but the tire will always be mounted to roll with the arrow pointed to the front of the vehicle..(and yes, that does mean you can go against the arrow when the vehicle is in reverse) So once the tire is mounted on a wheel it can only fit on one side of the vehicle according to its rotational arrow.
To move a tire from the left side of the vehicle to the right side of the vehicle the tire must be dismounted from the wheel and remounted on the other side with the inside of the tire from the other side becoming the outside of the tire when mounted on the opposite side of the vehicle.
There, that should completely confuse the issue!!!