Anyone know if it's possible for the L15B7 turbo VTEC engine from the Civic, Accord or CRV to fit in a 2003-2007 Accord?

 

For enough money, anything is possible; that said, why would you bother? The cost of making such a swap will be several times the value of the car the engine is going into, and even then, the car will not be any better than it was with its original engine, in fact, if the Gen 7 Accord is a V6 model, such a swap will make the car slower.