This CLI tool allows you to merge Lighthouse measurements and view them in the Lighthouse user flows view.
$ npm install -g lighthouse-flows-generator
$ lighthouse-flows-generator generate --urls "https://web.dev/" --urls "https://web.dev/blog/" --urls "https://web.dev/compat2021-holiday-update/"
or
$ lighthouse-flows-generator generate --files "./1.json" --files "./2.json" --files "./3.json"