@mbos Not sure if you mean wireless or wired?
I use wired headphones exclusively so I looked around on eBay and found adaptors that not only allow 3.5mm jack plug use but can simultaneously charge the phone with a USB C port too.
Just make sure that the type of adaptor you get works with Pixel phones. Some don't and I found this out after buying some that don't work. I have two types - a single USB C plug with two wires off of that - one to the 3.5mm jack and the other to a USB C plug. The other type is a tee piece configuration where one end is the 3.5mm jack plug and the other end is the USB C port.