This documentary was first reported on in October 2018 by Stewart Clarke in Variety: "Chaka Khan and Prince Feature Documentaries Launching at AFM"
Feature documentaries about Chaka Khan and Prince are on Kew Media Distribution’s slate for the AFM. Kew is building a profile in music documentaries, launching “Chuck Berry” at Mipcom and recently sealing deals with Showtime and Sky for “Teddy Pendergrass – If You Don’t Know Me.”
In Michael J. Kirk’s “Mr Nelson: On the North Side,” Spike Moss, a musical mentor of Prince, talks about the origin and influences that shaped the star’s musical skills. In turn, musical icons including Chuck D, Macy Gray and Chaka Khan recount stories of Prince and how he inspired them. It is the latest factual project about Prince since his death in 2016.
However, Michael J. Kirk was originally planning another documentary, "Prince: R U Listening?", as reported in November 2016 by Andreas Wiseman in Screen: "Prince bio-doc, Robert Pattinson crime-drama score deals":
Directed and produced by Michael Kirk (Find Your Groove), Prince: R U Listening? is set to chart the musician’s early years and rise to super-stardom as seen through the eyes of his bandmates, friends and family including Dez Dickerson, Prince’s first guitar player and Andre Cymone, Prince’s close friend and original bassist.
Contributors will also include Bono, Mick Jagger, Billy Idol, Lenny Kravitz and Sheila E. The film is due to be relesed in Q2, 2017.
This documentary never appeared, most likely due to him being unable to secure the rights to various Prince tracks from that era.
https://www.facebook.com/OfficialRobbyKrieger/posts/10156442870134075
https://kewmedia.com/film/catalogue/mr_nelson_on_the_north_side.html
https://kewmedia.com/news/press_clippings/prince_documentary_boosts_kew_medias_afm_slate.html
https://www.thefilmcatalogue.com/films/mr-nelson-on-the-north-side-1
https://tbivision.com/2019/01/21/natpe-hot-picks-mr-nelson-on-the-north-side/
https://variety.com/2018/film/news/chaka-khan-prince-documentaries-launch-afm-1203006870/
https://kewmedia.com/news/press_clippings/prince_documentary_boosts_kew_medias_afm_slate.html
https://kewmedia.com/film/catalogue/mr_nelson_on_the_north_side.html
Robby Krieger (guitarist of The Doors) wrote a new song called "Music Speaks Louder Than Words" for the upcoming Prince documentary "Mr. Nelson: On The North Side":
https://www.facebook.com/OfficialRobbyKrieger/posts/10156442870134075
This documentary was first reported on back in October 2018 by Variety: https://variety.com/2018/film/news/chaka-khan-prince-documentaries-launch-afm-1203006870/
Back then it was described thusly: "In Michael J. Kirk’s “Mr Nelson: On the North Side,” Spike Moss, a musical mentor of Prince, talks about the origin and influences that shaped the star’s musical skills. In turn, musical icons including Chuck D, Macy Gray and Chaka Khan recount stories of Prince and how he inspired them."
In a recent announcement -- https://tbivision.com/2019/03/04/show-of-the-week-mr-nelson-on-the-north-side/ -- this was said: "“This film explores the man behind the hype – never has a film about Prince included the childhood influences in his life that helped create the genius that he was,” says director and producer Michael J. Kirk and producer Daniel D’Or, who cite exclusive interviews from key people that helped raise and encourage Prince. These include the director of The Way and community activist Spike Moss, as well as Chaka Khan, Chuck D and Macy Gray."
However, it is likely this documentary was originally announced in November 2016 by Screen Daily as "Prince: R U Listening?", since that one was supposed to be directed by and produced by Robert Kirk, with as its subject "the musician’s early years and rise to super-stardom as seen through the eyes of his bandmates, friends and family": (Source: https://www.screendaily.com/news/distribution/prince-doc-biopic-robert-pattinson-crime-drama-score-deals/5111737.article )
It looks like that concept was abandoned because they couldn't get the necessary audio and video.
See also: https://kewmedia.com/news/press_clippings/prince_documentary_boosts_kew_medias_afm_slate.html