VR multiplayer

You would need to use a 3rd party multiplayer library. You will not be able to use Oculus's Multiplayer architecture as it only links between a single title ID. The Rift and GO are two seperate title ID's.

Thx! And which 3rd party lib do you recommend?

photon and unity's embedded networking library should be adequate for most applications. My personal recommendation would be photon since they have a number of different integrations and hosting options to suite almost every need, thought you should definitely look into both and see what would work best for your project

@MikeF  are there any tutorails about this subject?

My project is developed for the rift but i want to use a second hmd, in this case a oculusgo for only viewing with no interaction what's so ever, maybe only a chat function with voice.