Sure, you can change the icons
You can technically change the icons on iOS and Android as a quick bandage for switching between platforms, but it won’t do much to achieve the experience either way. On iOS, you’ll have to make the Google icons widget-by-widget using the Shortcuts app, which sounds tedious until icon packs are widely accepted on the iPhone. Android itself has plenty of iOS-themed icon packs, but you’ll have to run another launcher to make it happen. Not to mention, people will catch on once you start pulling down that notification shade.
