@jbaert @sawaba Heya. Take a peek at @owncast :)
Otherwise, I‘m using an Atem Mini Pro (but with OpenSwitcher running on Fedora Silverblue). Also Companion App runs well on Linux for use with an Elgato Stream Deck.
For interviews/multi-person, we use StreamYard and RTMP from there to our Owncast instance (https://owncast.small-web.org).
Hope that helps. If you have any specific questions, please feel free to ask.