Vr Extended mode

HI i have an oculus rift Dk1 and an Pimax 4K vr headset and i was wondering can i make an vr game that runs in extended mode ...i tried the vr feature in unity did not work as i my headset only works in extended mode and not in direct mode

Thus i wanted to to create a vr game that runs in extended mode like Affected the Manor or Dont let Go...etc
that runs in extended mode which is supported buy both these headsets

Can some one please help me with this problem i am not a big shot...

Vr Extended mode