Weapon viewmodel changes are possible with VPK modifications, which require a VPK tool. You can look up a vpk modding tutorial on RU-vid or go to the Northstar discord server, the people there are way more qualified to give tutorials and modding advice than I am.
@@disposedshelf You can customize your crosshairs on vanilla with vpk modifications ,which require a vpk tool. I'm not the best person to explain how to do it so I'd recommend visiting the Northstar discord server.