I haven’t found a way to do it.
Windows gives you automatic accelerator keys, so you can do Alt+F then E and A.
You could also save the following as a user script:
local app=DoApp.DoApp()
app:doCommand([[File.Export?FilterID=AudioFileExportFilter]])
Or you could directly add a shortcut for File.Export?FilterID=AudioFileExportFilter if you don’t mind editing your key commands JSON file.