I don’t see why that wouldn’t work. From my understanding, most ball valves that have a directional marking on them have an eccentric or “c” shaped ball closing mechanism inside. So because of that, using them in the wrong orientation doesn’t allow for them to flow properly to the desired tuning unless the valve is completely open. In a ball valve without the flow marking, there is a uniform sized ball inside with a hole in its center. So this allows for flow and complete utilization of the valve to restrict flow to the adequate tuning in either direction.
But a cepex industrial ball valve (like the one BRS carries) has a flow marking on it because of it’s threaded seal ability. The valve has an uniform ball similar to those valves that are bidirectional. But that extra red piece or key to tighten the ball valve you received with the valve is the reason for that flow direction marking. The mechanism to receives that works with the key part is on one side of the ball inside the valve. And that is on the opposite side of the arrow head marking flow direction. It allows you to keep the pressure within the system upflow to the valve while servicing the ball valve if need be.