I host anywhere from 1-6 streams at a time on a custom built server… I’d doubt you’re going to get what you’re asking without a much bigger build. It doesn’t take a crazy build for plex but if you ever need transcoding the pi can’t do it. My most recent iteration was ~$1300 but the price was mostly storage.
There’s 240w usb-c on every common marketplace for US market, is that not the case for eu?