You could if the host domain acted as a VPN/proxy

the cloudpilotemu project can use this host browser as a proxy thing so you can sync your emulated (in the browser) to your PC as well as give the emulator internet access, likely one way to have a browser in a browser.

I didn't try it out, though, i just read it in the documentation.

There is WebKit browser in browser: https://trevorlinton.github.io/

That's not a browser (even if you renamed it to "webkit browser"), and not working

Technically it is a web browser engine (WebKit) ported to JS and it works in the latest Firefox (shows a tiger).