How to get 2 audio sources on headphones?

I'm trying to get 2 separate audio sources to play on my headphones at the same time. How would I go about this? Is it as simple as hooking up a y-cable to my two outputs and then plugging it into my headphones? All the cables I've found seem to be for splitting one audio source to 2 headphones so I don't know if it would work in reverse.

All I need is audio out not worried about mic. Years ago I had a gaming headset that had a little volume control with a line in/out attached to the cord (meant for a mic) that let me listen to a separate audio source through an aux cable, so I think this should be possible.without a mixer.

The audio sources would be a ps5 controller and a PC If that matters.

What do I need exactly? Thank you.