Well yeah RMXP is limited which is what I mean anyway. Still going to be developing this on a PC. Which means it should be playable on any system which can emulate or run a .nds file, and should be able to be converted for other platforms.
Technically Nintendo wouldn't have a case against me, or any fan-game creator here as you need to be damaging a percentage of their sales. What we're creating is essentially fan-art to GameFreak/Nintendo, and if anything, we're boosting the esteem of the companies by doing so.