VR - Using HP G2 Controllers in Editor

Hello, i have a HP Reverb G2 headset.

When i enable HP Motion Control plugin to use my HP controllers → VR MODE is greyed out.

I did also try enable “Windows Mixed Reality” plugin.
But the VR MODE seems only be working with “Steam VR” plugin enabled alone.

I have SteamVR as well as Windows Mixed Reality Portal running in the background.

Am i doing something wrong, or is it a bug ?

Thank you