Yes, Oppo A5s does have a dedicated memory card slot. You can use up to 256GB MicroSD card in it. Besides, Oppo A5s also has OTG support.
Yes, you can play PUBG on Oppo A5s. We recommend you to buy 4GB RAM variant of Oppo A5s for the better gaming experience.
No. Oppo A5s does not have the IR (Infrared) sensor.
Yes, Oppo A5s does have the virtual gyroscope sensor.