My first reply was facetious, but I guess that whooshed.
To put it nicely, when asking an internet forum "Will a 2Rotor Motor from an RX-7 fit in my 06 2.0 Mazda3?", the answer is a complete and resounding "No."
If you put that question to the kind of shop that would actually be able to make it happen, the answer would be "Do you have $10k for a deposit?"
Whether the engine will physically fit in the engine bay is pretty much the least concern, so the fact that you're asking that first means you haven't got a clue what you're asking. Just being straight.