One oddity in the province names is Wissenland. Every other province has an easy explanation - river-land, middle-land, high-land, north-land, east-land. But Wissenland seems to mean 'land of the wise'. My theory is that when Reikspiel was being developed by fusing Unberogen with Khazalid, the Merogens of what would become Wissenland were the ones acting as go-betweens to the Dwarves, since they had good relations with the Dwarves even before Sigmar sealed an alliance with the High King. And when the maps were being drawn up and needed shiny new names in this shiny new language, I don't think it's a coincidence that the Merogens were the only ones that didn't get a bland geographical name for their homeland.
strictly speaking Wissen would directly translate as 'knowledge', so a very literal translation would be 'knowledge-land'.
land of the wise can be correct too, but that would be a less literal (and probably higher quality) translation