It feels like we've had A LOT of announcements about this year's Arrowverse crossover and The CW and DC just made on more by revealing that this year's crossover will be titled "Elseworlds."
Elseworlds was originally the name of a DC comic run that ran from 1989 until 2010, that put twists on all the DC superheroes we know and love like Gotham by Gaslight Batman and Superman: Red Son.
What we can infer from this title is that this may be DC and The CW's way of having Batman characters in the Arrowverse without directly having an actor don the cowl as the dark knight.
Legends of Tomorrow and Black Lightning also aren't part of the crossover this year, which may imply that the crossover won't feature multiple timelines or universes like the past few crossovers, but may explain Batwoman being introduced.
This year's Arrowverse crossover will take place across three nights, starting on Sunday, December 9 on The Flash at 8, Monday December 10 at 8 with Arrow, and wrapping up with Supergirl on Tuesday December 11.