if you mean running the chart on majdataedit, you can change the notesounds in the majdata program folder (Majdata4.x.x\Release\SFX) As for AstroDX it is currently not possible to change note sounds
it's really funny because despite this being "not maimai" it's surprisingly well made visually too but it looks like you could actually play most of it i mean yeah it's a really odd chart for a maimai but still the last part is ex notes, and everything else looks really fun i was pleasantly surprised! really nice chart!