I have an HP Envy X360 15-ee0358ng myself.
The Surface Pen works great! Pressure and tilt sensitivity are just right, the eraser function on the back of the pen works too, all the buttons do exactly what they're supposed to and I don't have to reconnect it every time I reboot - quite the opposite, I've never had to connect it, the thing recognises it straight away like this
I don't know what you have haha

I have now tried it out myself and it works pretty well. I can't get the top button to work, but everything else is tip-top.

no, you can't