when using power steering pump to drive clutch slave cylinder?

You're a moron

automatic trans

What are you trying to do? Make the clutch lighter? As you've gone off on some strange power steering pump tangent look at how a hydro-boost works or the way Nissan did it on GU Patrol was to add a vacuum booster to the clutch. Probably easier to resize the master and slave cylinders

Designing that would work but would cost more that the car. Nothing currently exists for such a task. Hydraulic clutch was the answer to hard to press clutches, modern cars have this. I have converted cable and linkage clutches to hydraulic with great results. Sizing the clutch master cylinder to the slave cylinder effects effort and travel as does the leverage the pedal has on the master and the leverage the slave has on the clutch arm. I have learned thru trial and error with the goal of a reasonable pedal effort. You would have to be real good at math to juggle all the numbers on paper.

If you made it easier than what cars come with today I would expect it much harder to release the clutch; without the resistance it currently has your leg would be twitchy. Holding pressure while raising leg is easier than with no resistance.

Sizing your master cylinder just a little larger in diameter would make a softer pedal but will also work faster and overtravel.

Get an automatic.

Never heard of that one, and can't see how it would work. In fact you may be able to get a servo for your clutch, try asking the people who adapt cars for the disabled. Or simply change to an automatic.

Never heard of a power steering pump also controlling the clutch slave cylinder. As a matter of fact they use two different fluids.

change your car ..easier than your option