Thank you.
My thoughts exactly.
There is plenty of other Euro compliance stuff that is also not checked, along with a fair bit of 'Construction & Used legislation. Emissions, lights, exhausts, seats etc are often changed in the UK.
The only issue is insurance, but if the insurer is informed and agrees to underwrite, it isn't a problem. Depends how enlightened they are. The chances of ABS preventing an accident in a bike like the Classic are tiny, given its weak brakes, wheelbase, weight and likely rider profile.