It's been covered in lots of threads, so I'd try the search, but a few obvious items that are different on euro cars are mirrors, smaller bumpers, no rear quarter lights, front quarter lights are smaller blinker repeaters, rear deck louvres are different, no exhaust diaper, flash to pass lights, different grill, different injection system, no cats, etc.
I will try for QV only: Exterior: 1. Engine cover louvre style 2. Markers on rear quarter panels 3. Exhaust "diaper" 4. Bumpers front and rear 5. Louvre colour on both engine and hood covers and behind headlights 6. Side mirrors 7. Driving lights under front bumper (edit: it's actually flash-to-pass lights) 8. Side blinker style 9. Rear fog light(s) 10. Emission decals on windshield and in engine bay 11. Front grille cavallino Interior: 1. Instrument panel 2. Safety belt receivers 3. Gauge units (UK and US are the same though) 4. Rear trunk size and shape Mechanical and body: 1. Engine and the ECU control systems 2. Emission system 3. Front hood latch numbers 4. Rear trunk tool kit strap 5. Fuse boxes Others: 1. Various identification plates and placements 2. Chassis number and the check digits 3. Engine number 4. Lights control stalk operations There should be many others I reckon.