Yes, Vivo Y91 does have the dual rear camera set up. It has 13MP + 2MP rear camera set up.
Yes, Vivo Y91 does have the App Clone support.
Yes, Vivo Y91 does have the virtual Gyroscope sensor.
Yes, you can play PUBG game on Vivo Y91 easily. Please check the following video which will give you more idea about the gaming performance on Vivo Y91.