For example, I have this config: I want to tell Webpack that this external is just for app.js and not for preview.js. is there a way to do that with externals or some other plugins.

module.exports = {
  entry: {
    app: './src/app.js',
    preview: './src/preview.js',
  },
 externals: {
    internal-lib: 'cdn.internal-lib',
  },

};