I’m going to try to answer the question as asked. Please in no way interpret this as me endorsing a Glock USA action to be safe in any way.
From a stand point of potential to fire when cocked and trigger not pulled, Glocks are safe. There is little to no stored energy until pulling the trigger.
Thus shortening the stroke is basically not possible….because you have to pull it to build the energy to release it to fire.
I gained all my knowledge on the Gen 3, but it looks similar today. I would tell you that like most trigger mechanisms, money is better spent on an experienced trigger tuning gunsmith than on replacement parts.
First, remember that much of the creep or better phrase junk felt in a Glock trigger pull comes from frame to slide looseness. That really cannot be fixed as far as I know.
Next, what trigger do you want to feel? I preferred the smooth one with the dingus slightly lowered to be a little more flush with the face. Others prefer flat face, serrated, wide dingus, etc.
10 min trigger job: Polish all mating surfaces and lube lightly with gun oil. These are trigger surfaces, so don’t change the geometry!
Then really polish the trigger bar well where it mates to the connector. No geometry change, just glass smooth under magnification.
Do the same for the firing pin block and where the trigger bar touches it. Try the lighter spring here…..I found little effect and changed it back.
You can change the connector, but that changes the geometry and thus the max force pull length(creep). I found the standard one was best.
Increase the trigger spring to get the pull weight down or up. Get a couple and just try them. It changes the overall feel.
Striker spring. This reduces pull at the expense of reliability. I cannot tell you where reliability will suffer, only that what ever tests well on range day has the potential to go bad when you need it.
After all this, I had a smooth 5.5lb trigger with 2lb take up and a reasonably hard “wall”. It was not a 1911 trigger or S&W revolver trigger. Not even close, but it was ok.