Support ESM in next.config.js

I'm making some optimation on nextjs project and need to has type: 'module' on thepackage.json file. But then got the error

Error [ERR_REQUIRE_ESM]: Must use import to load ES Module: my_path/next.config.js require() of ES modules is not supported.

Seem next.config.js is not support ESM yet. The issue already discussed here: https://github.com/vercel/next.js/issues/9607 but I can find a solution yet. Any help guys?

I'm using: node v12.17.0 next 11.1.0

And here is my next.config.js

import withLess from '@zeit/next-less'

const nextConfig = {
  target: 'serverless',
  productionBrowserSourceMaps: true,
  webpack5: true,
  onDemandEntries: {
    maxInactiveAge: 1000 * 60 * 60,
    pagesBufferLength: 5
  },
  lessLoaderOptions: {
    javascriptEnabled: true
  },
  trailingSlash: false,
}

export default withLess(nextConfig)

My package.json file

{
  "type": "module"
  ...
}

from Support ESM in next.config.js