But her offer was "declined" by Harries.
While Fergie divorced Andrew in 1996, the pair have stayed close friends and often attend events together. They have two daughters together, Princess Beatrice and Princess Eugenie, and one grandchild, Eugenie's baby son August.
She lost her royal title when she divorced Andrew, but she retained her Duchess of York title. But Fergie is now an established children's author, even hosting her own YouTube series Storytime with Fergie and Friends in which she reads children's stories.
Her first novel for adults is a romance novel titled Her Heart for a Compass, due to be published on August 2.
Netflix did not respond to a request for comment from Insider.
Sarah Ferguson was delighted to see her 1986 wedding play out on screen in the latest series of The Crown, with Jessica Aquilina playing her opposite Tom Byrne as Andrew.
She told Us Weekly magazine she thought it was filmed "beautifully".
"The cinematography was excellent. I loved the way they put my wedding in as well."
The duchess, 61, has also admitted she's "obsessed" with another Netflix series, Bridgerton.
"I adored Bridgerton so much that I watched it twice, deliberately. I'm obsessed with it.
"I think Daphne is a terrific character, as we see her learning about life. I love the way she learns to use her strong voice. It chimed with me because now is the time for women to speak up.
"The costumes and set designs were incredible too. The way Betsy Beers and Shonda Rhimes have created Bridgerton is fabulous, and I was really impressed."