This sequel is going to cost a lot of money.

Source: Crazy Days and Nights

There is interest in both sides, but the giant conglomerate is more interested in music from this A+ list singer, than her acting.

They are not sure about what amounts to stunt casting.

Lady Gaga

Harley Quinn – Joker: Folie a Deux

Lady Gaga confirms Joker sequel casting, to star as Harley Quinn

Singer-actor Lady Gaga has confirmed that she will be starring opposite Joaquin Phoenix in upcoming movie Joker: Folie a Deux. The film is sequel to 2019’s Todd Phillips-directed anti-hero character study Joker.

Gaga announced her casting in the Warner Bros project via teaser she posted on her Instagram page. The video clip is set to “Cheek to Cheek”, the song Gaga famously covered with legendary singer Tony Bennett.

Reports of Gaga’s casting as Harley Quinn have been doing the rounds ever since Phillips confirmed in June that he was working on the sequel with Phoenix returning in the lead role. Unlike the dark and gritty Joker, the sequel is being created as a musical.

https://indianexpress.com/article/entertainment/hollywood/lady-gaga-confirms-joker-sequel-casting-harley-quinn-8072068/