What are your opinions on its current name? He named it "Ziffie", resembling to "ZiFfiE", which means "Zero Fusion Editor".
I personally think it should be "Zero Fission". Having a hint to both GBA Metroids; Mission resembling to Fission, and Fission to Fusion, while still describing exactly what the editor does: Takes the game apart.
i would like to play through Fusion with ZM's engine and viceversa.
They already share the same engine (Wario Land 4 if I'm not mistaken?), it's the set of physic (and other) variables that differ. I'm not sure if this editor will have such a functionality (I'm not much into romhacking so I wouldn't know), but if it will, it'd be very nice to fool around with it.
What upsets me more is that it'd most certainly be impossible to fully recreate M2 RoS's environment due to the lack of respective metroid behaviour code and graphics (thankfully, most of the other enemies from there exist in Fusion). Otherwise it'd be a very cool project.