There is no other hamburger fast food restaurant except Burger King in Terminal 2 of Pudong Airport. You can consider Burger King on the second floor of Pudong Airport, and then go through the security check. You can also consider going to eat in Pushengda after the security check. If you really want to eat KFC, you must go to KFC in the transportation center about 400 meters from T2 pier.
The following are the brands of commercial catering in Terminal 2 for your reference.