2002 Corolla 1.8l ECM replacement

We have a 2002 Corolla that needs an ECM. We have found one on ebay that is identical to ours, all numbers match. Does it have to be reflashed or can we just plug and go? Thanks!!

I don't know for sure, but read this article:
https://mechanics.stackexchange.com/questions/4190/installing-a-used-ecm