As you have said, Raiden can easily escape Mileena's offense with his teleport. He can also teleport or dash forward on reaction when he notices Mileena going into the animation for her teleport kick, or do a superman. Zoning him with instant-air sais is pretty pointless as well.
NEVER go for a jump-in. The Raiden player who knows anti-airs will score a s1 - Vicinity Blast followed by a full combo for around 30% potential damage. Jumpkicks would be wise, but they lose to his armored EX Electric Grab which also nets him a combo.
Honestly...I don't see this match-up being even. I can see how Raiden effectively shuts down so many of Mileena's options, from far away and up-close. The best I could tell you to do, as Mileena, is try to check him with d4, and
maybe punish a teleport you read with her Ball Roll. Remember, Raiden's teleport almost can't be punished on reaction...it has to be on read.
I think I'll get some Raiden and Mileena pros to speak up on this match-up for you, maybe they'll have better advice.
Jer
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