Hmmm... Oddly, I have spent a bit of time in Scotland, (3 month stints, about 4 times - LOOOOOOVE it there!) and... No, I cannot recall even one person there saying or doing anything like the above scenarios - not too me, and not in front of me. I mean, maybe it happens, but I did not personally experience it at all.
And, I lived in Ireland for about 6 months, at 3 different times in my life, and I am quite sure that no one there did it either - at least not to me. Actually, in Ireland, as a kid, at age 12, in Cork, the other kids loved my accent. I remember feeling 'popular' and 'unique' for the first time in my life! I did not get picked on at all.
I do have one friend who lives in Scotland, and her teenaged American born son gets picked on quite badly for being American - but he is a bit older than I was and a boy, and I think in general many older teenagers just pick on each other, everywhere, about anything. He is about 15.
In Scotland and Ireland, I did hear people, very often, slagging off the English!
But, not usually to their face - it would generally be done behind their backs.
It happened more in Ireland than in Scotland, but it did happen in both places.
Sigh. Does everyone need someone to pick on?
I was managing staff that I chose and hired for Royal Ascot a few months ago, and one of the people I hired was originally from Manchester. By chance, he was the only Northerner in the group. The other guys, who were mostly mostly local - from Surrey and London - they totally picked on him. In a 'friendly' way. But, it was constant. I actually had to say something to them and put an end to it because it was upsetting the guy. I could tell. He never actually 'said' anything to them, or to me... He just tried to laugh it off, and he sometimes ever so lightly teased back - but I could tell he was getting angry.
So, one day, me and the guy from the North ended up taking the same train from Ascot back to London after work, and he thanked me for dealing with it. And I asked him if they had stopped doing it, and he said something like, "Well, no, because they will never stop, but they have at least stopped doing it as much, because they don't do it in front of you." And, I asked him why they mess with him so much for being a Northerner. And he just smiled and said, "I guess it is just the way the Brits are. Everyone needs someone to pick on. In Manchester, we pick on the Londoners."