You can use OBS "Custom browser docks" to integrate the chat in your OBS while you are streaming.The livechat plugin offers a way to create long term token that can identify you automatically to join the chat, so you don't have to enter your password in OBS.
To do so, just use the "{{% livechat_label share_chat_link %}}" feature, and open the "{{% livechat_label share_chat_dock %}}" tab.From there, you can create a new token using the "+" button.
Tokens are valid to join any chat room. You don't have to generate separate tokens for each of your rooms.You can also customize the nickame that will be used by changing the `n` parameter in the url.
These tokens can be used for other purposes, as connecting to your account with XMPP bots or clients.This feature is not documented yet, and not officially supported. So use with care.
You can use the [social_stream browser extension](https://github.com/steveseguin/social_stream#readme) to mix multiple chat source (from Peertube, Twitch, Youtube, Facebook, ...) and include their contents in your livestream.The compatibility with this plugin was added in recent versions.