The A/T crank pulley does have a 50mm hex hole, which I believe is shared with most other Honda/Acura models. This is why the 50mm version is much more common.
I believe the M/T pulley has a 45mm hole as you say which is harder to find. Quick search shows the Performance Tool W80496 is a 45mm tool, but the 1/2" drive end is thin and might break before the crank bolt comes loose. That design seems to be the only readily available version besides the OEM one which is expensive, but another option.
I'd also highly recommend getting a 19mm weighted hex socket for the crank bolt removal, your impact gun will struggle with anything else. Otherwise you'll need a very long 1/2" or 3/4" drive breaker bar and all your body weight which might also break the pulley holder tool. Make sure you follow the factory torque procedure and oil the bolt before reinstallation, and consider replacing the crank pulley/harmonic balancer if old as well to preclude damper separation.