What is the difference between "striezen" and "triezen"? Duden shows a similar meaning for both.
This word doesn't exist in standard German. It is a colloquial word used only in northern parts of Germany. It means to irritate/plague/torture someone but also to steal something
This word also is a colloquial word (so you won't find it in newspapers), but it is used in southern parts of the German sprachraum. (I live in Austria, and here this word is well known.) I have no idea if it is known in northern parts too. It only means to irritate/plague/torture someone. It has not the meaning of stealing.