There's actually 3 different forms of crash stop depending on propulsion and rudder layout.
1. Full reverse as fast as possible, this is for both turbines, and pistons, for both you have to stop the rotation then reverse, which depends on size of reverse turbine/ water resistance. It is notable some turbine powered ships did not have reverse (HMS Dreadnought is a prime example)
2. Turbo Electric full reverse, this is by far the fastest unless combined with number 3 as unlike reverse turbines/reversing pistons you do not wait for the turbines to stop if anything you want them to spin faster to give you all the power possible to your electric motors. You get immediate and instant full reverse power to your electric motors, if you have 150,000 horsepower ahead you got the same in reverse, the biggest limiter here is that you don't twist off your prop shafts. It is also of note that propellers are not as efficient in reverse so even though you have access to full power it does not mean you can use it.
3. Closing the barn doors, this option is only available on 2 rudder ships with the rudders under local damage control stations. This is an extreme method of stopping that will stop a ship faster than any other method mentioned unless combined with 2. When the USS Wisconsin tested this she almost ripped her rudders off, and had chronic rudder issues the rest of her service life. Basically they turn both rudders to full amidship, USS Wisconsin when she tested this went from flank to a full stop in 2/3rds of her length as measured by a crewman who threw a chunk of wood overboard at the bow and by the time the ship stopped it was abreast the number 3 main turret. If you want a ship stopped, there is no way to stop one faster, but you will hello kitty something up in doing so that will require replacing the rudders, the steering gears and the mounts in order to fix properly.