One Take News has done some digging and while this remains unconfirmed and is based heavily on speculation, it looks like we may be seeing Killer Moth in the movie. The outlet came across an IMDb listing for a stuntman by the name of Matt Da Silva who’s doing stunts for the villain.
Of course, IMDb can and often is inaccurate with its listings, so don’t take this as set in stone for now. But that being said, it wouldn’t surprise us at all if Killer Moth were to appear in Batgirl.
Source: One Take News