Saw this on io9's morning spoilers daily digest.
https://thedirect.com/article/batgirl-movie-dc-multiverse-connections-exclusive
However, El Arbi did hint that the film will indeed connect to DC's emerging Multiverse somehow, while also suggesting that fans will "have to see the other [DC] movies to understand what happens" in
Batgirl and to grasp how the Multiversal madness works on this side of the comic book movie landscape:
"Well you know, we’d sort of give the same answer, because we would also ask, 'Oh, you have J.K. Simmons from the Snyderverse and we got Michael Keaton from the Burton-verse. What’s the situation there?’ And they would say, ‘Don’t worry about it. We got a plan.’ They never really explained that aspect to us, but I guess you’re gonna have to see the other movies to understand what happens, why the reason is that we ended up in sort of a spaghetti of Multiverses in that aspect. It’s gonna be a delicious spaghetti, I’m sure of that.”
Some of these reports have me wondering if they aren't putting the cart before the horse sometimes when even the creators seem to be in the dark over the big picture of the machine. Maybe that's just part of the unique nature of working as one part of a big franchise.