WebCord is an “alternative client” for Discord, although it’s just running the Discord webpage in electron. Recently it updated its electron version so it supports sharing audio as well as video.
I tried it out today on mint (x11, pulseaudio) and it works flawlessly.
And Vencord has a desktop client “Vesktop” which works like Webcord, with audio in stream too. No presence detection but notifications have worked for me