Output of two stereo signals via 5.1 onboard

My computer has a mainboard from Gigabyte (B550M S2H) with onboard Realtek 5.1/7.1 sound.

I would like to output two stereo signals separately from each other. I’ve done this before on another Windows PC. Signal 1 was music and went to the speakers via cable. Signal 2 was speech from a video call and went to the headphones via the second cable.

Is that also possible with Linux? What do I need for this and where can I find information about it?