OBS-STUDIO works on OpenBSD i have compiled it
I had to convert all sndio inputs to mono or else i would have a strange noise !
Don't try to add video capture device for your webcam its pretty unstable and can crash the system, instead add a Window Capture and capture ffplay window remember to add the noborder switch to ffplay if you don't want titlebar ! Also remember to uncheck capture mouse cursor !
My mic needs a little amplification but obs removes any noise very successfully
Not like i needed obs ffmpeg does its job very nicely i have streamed live with ffmpeg before
To capture the desktop /monitor you just add an sndio input and replace "default" with snd/0.mon , snd/1.mon for usb etc etc you know the drill. It is better you restart obs-studio to make this work .
This was a live streaming just in case you wonder if obs-studio works for live streaming.