I'm with Clark_Kent. A BoP sequel won't be a priority, but if the mutual finger-pointing at WB ends up pointing at marketing rather than production (and I'm firmly in the camp that poor marketing caused this movie to underperform, rather than the quality of the movie itself), then I can see another Harley Quinn movie coming, though likely with a smaller budget.
Another Birds of Prey movie is more unlikely, but I can see WB wanting to use them in other upcoming movies set in Gotham.
Now that I think of it: I now have two superheroes that I'd really would like to see make at least some appearance in WW84. The first is that Eugene Brave Rock returns as Napu (aka Chief). The other is that Dinah Lance's mother appears as the original Black Canary. Put Dinah as being born around 1990, and her mother born around 1965. That makes it plausible for Dinah's mother to have met Wonder Woman early in her career, give birth to Dinah, and then die while Dinah is still young enough to remember her.