Congratulations on two excellent choices of university. As others have already said, don't expect to see many kilt-wearers at either place, unless there is a rugby game on that is. But that is no reason to stop you wearing yours. You never know -you might start a trend!
Of the two universities you will probably find more Scots in Aberdeen as Edinburgh is very popular with our southern neighbours (known in student circles as 'Yahs' - "are you coming to Champagne Charlie's tonight?" - " Oh ya"). My then student son said they tended to move in rather exclusive circles, not mingling with the locals. Naturally they are not kilt-wearers.
My other son went to Aberdeen and enjoyed it greatly. Too much partying I think but he did manage a degree in the end.