Minnesota has almost as many tree-huggers as California, they just have more snow.
So I'm pretty sure the emissions will likely be just as strict.
As for the registration...in my situation, I told the Pennsyvania dealership where I bought my SS new to use the Virginia sales tax rate and they cut a separate check to the VA DMV so the taxes were still rolled into my financing. Maybe this situation would apply the same for you to avoid getting hit twice somehow.