Personally I'd just get a different shaft so that the sprocket is behind the backing plate, and the pulleys become near perfectly aligned by that default, it would most likely require some minor shimming to the driven, easier to shim by a few 16th's than reconfigure the entire assembly
With that orientation the pulleys will not be near perfectly aligned.
During upshift the belt will be moving inboard at the front while its moving outboard at the rear.
During downshift it will be the opposite.
Some people claim that the driven pulley will "float" laterally to follow the drive pulley.
There may be some amount of that but I believe it would be minimal.
The pulley, under tension, will resist being moved with that kind of leverage and will for sure lag in alignment, if it moves at all.
In the snowmobile world, some claimed that allowing more than spec'd slack of the driven pulley mounting would let it float a small amount, keeping better alignment and saving belts.
That was to correct for the engine twisting on the mounts and even the success of that very small amount was debatable.