It's actually not that hard to read "the MML-data" in a song. The thing is you'd have to convert it back to AMK-format (in the case of AMK ports) and other games obviously don't use the AMK engine.
If I recall correctly VitorVilela even made a simple tool that tries to convert N-SPC songs into AMK format.
If I recall correctly VitorVilela even made a simple tool that tries to convert N-SPC songs into AMK format.