The actress, who voiced Mulan in the 1998 animated movie, surprised fans over the weekend - when the live-action blockbuster was finally released on streaming site Disney+ - by making a cameo at the end of the film, but she reveals she was offered a much bigger part.
"I was going to be the potential mother-in-law for the matchmaker scene," she tells the New York Times.
But she had to turn down the job because she couldn't commit to a month-long shoot.
"They (Disney bosses) needed me to be out there for a month just in case," she explains, adding her "Agents of S.H.I.E.L.D." TV producers wouldn't let her be out of action for so long.
"(They) just threw up their hands (and said), 'We can't lose you for a month!' " Ming-Na adds. "I totally understood, and I'm always very Zen about this stuff. I said, 'Look, if it was meant to be, it was meant to be. We all tried, and it's too bad.' "
But director Niki Caro refused to pass up the chance to work with the original Mulan and came up with another idea.
"(They) came up with this great idea, where instead of shooting an entire scene, I'd just make a cameo at the very end to announce Mulan to the emperor," the actress reveals. "I thought that was very appropriate and just wonderful, a little Easter egg where I could pass the baton. And this time, they only needed me there for a week. So it all worked out!"