No. Redmi 6 does not have the IR blaster support.
Yes, you can play PUBG on Redmi 6.
If you use the supplied 5W charger, it charges to 18 percent in 30 minutes and 35 percent in an hour.
No. Redmi 6 does have a dedicated MicroSD card slot and 2 other slots for SIM cards.
If your budget absolutely can’t exceed the Rs. 8,000 mark, go with the Redmi 6 without any concerns whatsoever.