Steam beta client recently added support for DualSense controller. Using USBPcap I was able to get a trace to see how it work. The DualSense use report 0x31 for config and buttons reports. Using the native PS5 mode vs the HID mode allow using the LED and Rumble. BlueRetro now support the DualSense rumble. The LED support for Steam didn't work for me so it's still missing on BlueRetro.
On a different note, PSX & PS2 support is progressing very well. I'm also working on adding keyboard & mouse support for systems already supported.