Kryptonians: Zod, Power Girl, Superboy, Supergirl, Superman
JL Team: Captain Atom, Captain Marvel, Hal Jordan, Batman (Insider Suit), Wonder Woman
All the Kryptonians have come under the mental influence of some alien being who has made them believe everyone on Earth is evil and their enemies. As a result they're now attacking everyone they see and have no morals. Batman sees what's happened and quickly puts together a team to stop them. As soon as he has the team, his satellite spots the Kryptonians attacking a city. They then teleport in to fight. Everyone is pre-52 versions.
Kryptonians: No morals, believe the team are enemies sent in to kill them.
JL Team: In character but highly motivated to win. 5 minutes prep time and get the drop on the Kryptonians.
Can the JL team take down the Kryptonians? Win by KO, death, or incapacitation. No BFR.
EDIT: Only standard equipment allowed. Prep time cannot be used to go get/build/borrow any extra equipment.