As part of the Brexit agreement with the EU, in some areas of we have agreed to adopt equivalent law or directives at least for some period of time. I don't know if this one such area or not.
But as Otherclive has pointed out, if we want to be able to export cars manufacturer in the UK to the EU, then those cars would have to comply with EU regulations.
But not all EU redtape was unwelcome, and if by adopting this technology into UK vehicles it helps to reduce emissions then we are likely to see it happen.