Not easily. Enabling playerstandardarmor.renderfirstperson shows all of your body in first person, not just the hands. This makes looking down impossible since all you see is your hips and legs, and looking at any angle will put your head partially through the fixed viewpoint along with anything like visors which looks odd.
I managed to get a neat effect by hiding everything except your hands and feet, but I wasn't able to do this client-side so it didn't work well and broke some weapons that stay in a fixed place in first person (Hammer, Wrench, Printer, Sniper Rifle)
