Although I haven't heard of anyone suing to stop it.
The rule or law or whatever in MN that allows ballots postmarked on or before Nov 3 to be accepted on or before Nov 10 is going to be dealt with by the 8th Circuit Court of Appeals this week. (Would be outrageous if they changed it because, well, we're less than 7 days away).
I did research the Wisconsin thing prohibiting early counting ... it's a state law, apparently long-standing (so at least legislation like that won't get passed in MN anytime soon. As opposed to some stupid judge that can act virtually instantaneously).
https://www.jsonline.com/story/news/solutions/2020/09/22/wisconsin-absentee-voting-surging-let-clerks-count-ballots-early/5864840002/
Editorial: Wisconsin should allow clerks to start counting absentee ballots before Election Day, Milwaukee Journal Sentinel, 9/22/20
... Wisconsins clerks have pushed for a change in state law that would allow them to open and place ballots into tabulator machines as they arrive in the mail. The tally would not be counted or disclosed until Election Day. Wisconsin law now requires them to wait until Election Day to begin counting.
Many states allow some form of early counting, according to the National Conference of State Legislatures. Colorado, for example, allows counting to begin 15 days before Election Day, according to the NCSL. North Carolina allows counting to begin two weeks early. States dont release results until Election Day and typically levy harsh penalties on anyone who tries to leak the tally.