After Brexit, and assuming no deal, I would imagine that EU students fees would default to the amount paid by overseas students – that is, much higher.
With a reciprocation deal, EU student fees could be anywhere between the current level and the overseas level.
UK university fees are amongst the highest in Europe even for Home students, with no prospect of change anytime soon. I can’t imagine why anyone would come here to study, unless they got a fully-paid scholarship to do so. I certainly wouldn’t advise studying in the UK: fortunately, I’m Irish and can send the offspring to EU universities!