An interesting article on implications for Ireland
"Meanwhile, the cornerstone of the peace settlement, the Belfast agreement of 1998, is being undermined. One of the key provisions of the agreement is that anyone born in Northern Ireland has the right to be a citizen of the UK or Ireland or both. What does that mean in the new dispensation? Can someone be both an EU citizen and not an EU citizen? Likewise, the agreement underpins human rights through the “complete incorporation into Northern Ireland law of the European Convention on Human Rights”. Though not strictly required by Brexit, the leave leadership is committed to removing the convention from UK law – in other words to ripping out a core part of the peace settlement."
Yes, this could be a big problem as there are a few nutters on both sides.