Wyntoun does not mention Sawney Bean. He very briefly mentions Christie in chapter xxxvii at line 5570 of the PDF from the link below. It does no more than mention a cannibal near Perth (ie St Johnston)called Crystene Klek who targets people to eat.

"A karle, thai sayd, wes nere there-by
That wald set settys comonwnaly
Chyldyr and women for to sla,
And swanys, that he mycht oure-ta,
And ete thame all, that he get mycht;
Crystene Klek tyl nane he hycht.
That sary lyff contenwynd he,
Qwhill wast but folk wes the cuntre"

It is possible that the much later legend of Bean in Ayrshire/Gallway had its roots in the story of Clek in Perthsire. The earliest there is any mention of Sawney Bean and his story is seemingly from the 18thC English sources. See the BBC Scotland link below.

There are no doubt variants but the usual story of Bean has him captured by a King James and taken to Edinburgh. That would need to be some date between 1424 and 1603. Much later than Bruce's time or the Perthsire story.

https://archive.org/details/orygynalecronyki02andruoft

http://www.bbc.co.uk/scotland/history/sawney_bean.shtml


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