In JLA, Katana is Diana's counterpart. I think it is a poor choice, Katana uses only a sword to fight. Granted it is magic but still they could of went with a better choice. I think they should of went with Isis (Adriana Tomaz). She is in Diana's power range and could reasonably beat Diana. Isis was a woman named Adriana Tomaz who was giving an amulet that when she said " I am Isis", she became a heroine. Black Adam gave it to her after he fell in love with her.
She is super humanly strong and is easily capable of lifting far in excess of 100 tons, putting her on the same level as Supergirl, Power Girl, Mary Marvel, and Wonder Woman. She is also incredibly durable and cannot be harmed by physical force unless the being she is engaged with is stronger than her. She is also totally bulletproof and bladed weapons shatter against her skin. She is super-humanly fast, capable of moving at speeds past Mach 10 on Earth. She also has far superior reflexes and agility when compared to normal humans, or even other superhumans. Isis is also able to mystically fly through the air at incredible speeds and can travel across and around the planet in minutes. Like the other Marvels, Isis possesses an immense degree of superhuman intelligence, allowing her to come up with solutions to complicated problems quickly. Unlike the other Marvels, Isis' powers focus on the control of nature. She has control over water, fire, earth, air and electricity and can control the weather and the lava within the Earth. These powers are tied to her emotions. When she cried, it began to rain and when she grew angry, enormous roses crushed the buildings around her. Simply put, Isis is nature and can control its every aspect. In addition to her manipulation of natural materials, Isis possesses the power of telekinesis, allowing her to lift objects, fire blasts of telekinetic force, and to create telekinetic shields. Isis' godly energies are able to heal nearly any wound that she has been inflicted (though she has died before) with surprising speed