FF6Tools - Browser-Based ROM Editor

Just curious if someday an option could be to load ff5 maps into ff6 and visa versa, and have it use the correct tile sets and properties and all that to have it nice and seamless.

In theory, that wouldn't be too difficult. The map layouts, graphics, and tilesets all have basically the same format. There are some details like transparency and tile properties that would probably need some tweaking. On the other hand, FF6 maps are designed for 16x24 character sprites while FF4 and FF5 maps are designed for 16x16 character sprites. If you simply copied a map from one game to the other, the sprites probably wouldn't line up properly with some of the map tiles.

With FF6Tools, I plan to eventually add import/export for raw binary data. This would allow you to copy a map from one game to another, although it would still probably take some trial and error to get it looking nice.