Use proxy with a basic authentication with Chrome and Selenium. This is a C# wrapper.
Chrome plugin generator for setting private proxies to use with Selenium
This module is based on https://github.com/RobinDev/Selenium-Chrome-HTTP-Private-Proxy and https://github.com/Luzaofa/CreateProxyExtensionHelper
It's for proxy with password. If you find that, that's the one.