There are enough teachers being laid off around the other 49 states to bring in all new teachers for the state of Wisconsin. I would likely step lightly here because you would have to bring each teacher into a room and offer a contract, then give them a day or two to accept or refuse. At that point...you’d advertise and likely find 20,000 teachers ready to step in. The only other issue is accreditation. But you could pass a simple rule that accreditation in one state is good enough in Wisconsin.
If I were a teacher in Wisconsin currently....I might start asking my union rep more questions and start to add up my expenses. If you owe money on a house...you might not want to screw up anything. Teachers don’t exactly have a second career to fall back on....and you might be homeless in Wisconsin....which means you move back in with dad or your brother...which might be acceptable there but I doubt it.