[noggin]

Hello,
I would like to add Live TV via Sat to my N2 Coreelec setup. TVheadend is planned as server and client.

Can you recommend me an usb fbc dvb-s tuner that is working with TVheadend? Is it possible to add oscam config as well?

I'm not aware of any USB FBC DVB-S/S2 (or S2X) tuners for PCs yet.  Oscam isn't really a topic that can be discussed here.

I've only ever seen single tuner USB DVB-S/S2/S2X tuners on sale - and they were for use with regular Universal LNBs (some may also support Unicable or Unicable II).  For multiple tuners you are really looking at SAT>IP or a PC with PCI-E tuners (I've seen Quad and Octo DVB-S/S2/S2X PCI-E tuners - but I'm not sure I've ever seen FBC stuff - that's still really only available in Enigma type devices)