A law permitting the killing of Scottish archers in York has not been explicitly repealed:
www.theguardian.com/politics/2007/nov/07/uk.queensspeech20072
However, the article points out that
""In most cases, the implied repeal argument would probably work," said Mr Coad. "Whatever people in York may think about Scotsmen with bows and arrows, they would have a hard time avoiding several centuries of homicide acts."
Presumably the laws permitting the killing of Welshmen in Chester and Hereford should also not be put to the test.