I don't know. My only thoughts are that any legislature can vote to enact any statute they want on any subject matter, and the respective executive government "can" or will operate within the framework of those statutes until the moment they're successfully challenged in a court with sufficient jurisdiction. But, someone has to sue, and there are suits that are quick and easy due to overwhelming precedent, and suits that aren't so clear that hinge on the headbutting of different precedent and possible new interpretations of constitutional law.

In the cases you mentioned, it's possible that other states would have standing to challenge NC and Wyoming and would have been successful in doing so but chose not to for some reason. I'm not clear on precedent either, but the fact that US states share such uniformity in who gets to vote suggests that precendent has filled in the apparent gaps.