How do I run next export with custom filenames?

I'm trying to export our site using Next. Prior to working with next we had a custom webpack build that would specify an output format so we can append a hash.

output: {
        filename: 'file-main.[chunkhash].js'
    },

I adjusted the next.config.js to have a customized webpack configuration like so:

/** @type {import('next').NextConfig} */
const nextConfig = {
  reactStrictMode: true,
  experimental: {
    images: {
      unoptimized: true,
    },
  },
  webpack: (
    config,
    { buildId, dev, isServer, defaultLoaders, nextRuntime, webpack }
  ) => {
    const newConfig = {
      ...config,
      output: {
        filename: '[main].[contenthash].js',
      },
    };
    return newConfig;
  },
};

module.exports = nextConfig;

When I try and next export I get this error

Build error occurred [Error: ENOENT: no such file or directory, open 'C:\repos\storefront-admin\storefront-ui.next\server\pages-manifest.json'] { errno: -4058, code: 'ENOENT', syscall: 'open', path: 'C:\repos\storefront-admin\storefront-ui\.next\server\pages-manifest.json' } info - Collecting page data .

Has anyone changed the output filenames successfully?