This is interesting. Wrapping the handle of a semi automatic pistol with paracord. I would be concerned about pulling it tightly enough so it does not come apart from recoil. If it works, I would image that paracord would provide a good grip, and may be a good improvement if you feel your polyomer pistil has a slippery grip.
I can’t say that we endorse any firearm modification and advise you to proceed at your own risk.