When playing Karma her default opening voice (when the game begins) is Irelia's "Irelia will prevail", Her joke, taunt and laugh are her own from what I've tested so far.
1. Pick Karma as your champion
2. Start game and listen to her comment "Irelia will prevail"
This happens multiple times throughout the game and I have replicated this in ARAM and Summoners Rift
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