@Harry
Since her name is written as ノール "Nooru" in Japanese, then I would lean towards Nord being correct, based on this page here: https://ja.wikipedia.org/wiki/ノール
Just a guess, but it's probably a French-derived name, based upon the French word for "north," in which case, Nord would be appropriate.
Alternatively, it could be based on one of the surnames listed in the article I linked, such as Knowle, Nool, Knoll, or Nohl.
I think it's probably safe to say it's not based on the Mongolian word for lake, нуур (nuur). Doesn't really fit with the setting. (https://en.wiktionary.org/wiki/нуур)
For what it's worth, the Names dictionary that Rikai is using says it's not Norl:
And... looks like it won't let me use the URL tags for some reason... Maybe because the links use non-English characters. So I simply got rid of the tags and people can cut-paste the URLs to get to them. At least I was able to link the image.