I'm not sure for a web or app export, but with nw.js in a desktop export you can get filenames with the listat() expression from a directory, and use that to build a list of your sound files. Then play by name.
I think for web/mobile export you'll need to manually create a list of sounds you want to play. I'd make a little side utility to create this list for me with nw.js if it is updated often. Then I'd save the list and use that as a project file in my actual project.