The way I see it, if you weren't looking at the ground & kept the same airspeeds throughout the maneuver when turning either upwind or downwind it wouldn't matter at all except for any different wind gradients you're passing through as another poster mentioned.
But because you are referencing the ground track & not airspeed when doing that sort of maneuver at low altitude the wind direction matters.
Biggest scare I ever got ag flying was the same sort of situation - heavy as I'd just taken off with a full load, field rows were directly aligned with the wind, turning downwind. Couldn't widen the turn to keep airspeed up because of obstructions on both sides, so end up with basically zero airspeed at the top. Dropping back down into the field with plenty of ground speed but very little airspeed yet, aft cyclic isn't going to help there. Ended up about 6" above the dirt with rpm bleeding off before stopping the descent... Bad choice on my part getting into that situation, it was definitely a learning experience!