The layout is defined by what you set on your computer, it doesn't have to match what's on the keycaps. The only thing to look out for is ANSI vs ISO, UK keyboards have an extra key instead of a longer shift key so you'll want an ISO variant of the keyboard.
If you want some keycaps with UK legends, make sure they include a 1.75u right shift if your keyboard has that. Other than that, the keychrons have standard layouts.