Skype interviews are best done with purpose-built software such as Pamela. The upper two Pamela licenses, Business and Professional, will provide, at your option, split sound tracks with the two directions on different files suitable for post production filtering and adjustment. There are free ways to do this, but you are warned to avoid solutions that insist on delivering a mixed file or worse, only work in MP3. Never do production in MP3.
http://www.pamela.biz/en/products/
https://forum.audacityteam.org/t/help-recording-with-a-mic-laptop-and-headphones/35068/6
But that’s not how I did it. As an experiment, I joined two computers and a mixer and did a fully produced, live Skype show with music beds and full duplex, live connection (unzoom your screen to see the whole thing).
http://kozco.com/tech/audacity/clips/DeniseFirstPass-Edited.mp3
It didn’t go perfectly. I messed up one of the music connections, but would you guess that Denise and I are four time zones apart? I did cheat in one other area. My two Macs are slightly older units with full Stereo Line-In connection and will interface directly with the mixer. Windows machines and newer Macs will need USB adapters.
That’s how Pando is doing it on their podcast.
Koz