Is there a way to change the pitch of a sound in AGS through script?
There's only AudioChannel.Speed, if that's what you mean; if you mean changing pitch alone - that is not supported at the moment.
May be you could use a module (xm, s3m…).
But for this, AGS must be able to play a single pattern, not the whole module.
If AGS can do this , then you define differents patterns with all the pitches you want. The sample will be unique, and the patterns take a few bytes each, so even with quite large number of patterns, that's almost free.
But for this to work, AGS must be able to use specificities of modules. Not just play/stop music.