Dressed in black and wearing glasses, Phan was supported by three friends as she faced Burwood Local Court.
The court heard that Phan was studious, and was waiting to go to University of Technology Sydney to study a Bachelor of Nursing, and that she played Oz Tag and did cross country running.
"And she's carrying 394 capsules of MDMA? What irony," McManus said.
Phan's lawyer Cheryl Khurana told the court her client was "extremely remorseful and shamed".
Phan, who was dressed in a black Lacoste shirt, works four days a week at a Subway shop.
Khurana said Phan was aware a conviction could "well upset jobs prospects and her future".
"Her parents divorced after 21 years, her elder sister married in September," Khurana said.
"She felt obligated to try and help out in terms of finances. Her mother works two jobs, as a butcher and a retail worker."
After McManus rejected that defence, Khurana told the court that a "mutual friend" had asked Phan to carry the drugs into the festival in return for money.
McManus said Phan would be convicted but that she could be assessed for a community service order as punishment.
On December 8 last year, police arrested five festival goers including Phan on drug charges at the Knockout Games of Destiny at Sydney Olympic Park.
Callum Brosnan, 19, was found collapsed at Sydney Olympic Park train station early on the Sunday morning after the festival.
He was taken to Comcord Hospital where he died at 4.30am from a suspected drug overdose.
Police have not publicly revealed Brosnan's cause of death and it is not suggested he took drugs allegedly supplied by Phan.
Fifteen people were taken to hospital after the Knockout Games of Destiny, three were placed in an induced coma and 130 sought medical treatment at the event.
