I don't know much about ROM Hacking so I'm not sure, but I don't think it's possible. Gen 5 Hacking is still greatly uncharted territory, so unless you want to make a simple hard mode or dex replacement type of hack, Gen 3 hacking is superior in every way. With projects like the Complete FireRed Engine Upgrade, Emerald Battle Engine Upgrade V2 things like Mega Evolution, Z-Moves and many more mordern features are accessible to everyone and you can literally just install one of these and move one to scripting, spriting and storyboarding... Its that simple.