Would there be a situation like the Bat embargo of the DC animated universe? (Justice League and Teen Titans couldn't use Batman villains because the WB's "The Batman" show was using them)
Could they mention Supergirl, Green Arrow, and Flash, and even have their own versions of those characters?
"The plastic tips at the end of shoelaces are called aglets. Their true purpose is sinister."
It's supposed to be a subdivision of Wayne Enterprises. Alan Tudyk's character is named Van Wayne. I'm thinking he's Bruce's cousin.
Crimson Fox is supposed to show up. So Justice League could be referenced.
Note Season 1, Supergirl creators said that Supergirl was part of DC universe's cinematic universe -with Superman/Batman etc. But now that it's on the CW/they have their own Superman. Supergirl may be part of her own universe. Arrow/Flash/Legends are part of their own Universe.
There's one DC character that's going to have some issues.
Constantine - Remember there was Constantine series on NBC 2 years ago. Ran 13 episodes before it got cancelled. After the series was cancelled, CW was able to work out at deal /get Matt Ryan to reprise his role for an episode of Arrow.
It's been announced that Matt Ryan is once again reprising Constantine in a web series on the CW.
He's magical/can cross dimensions. Of course, if they wanted to tease everyone. They could bring in Constantine. Imagine if they got Keaneu Reeves, Matt Ryan and/or someone else to play him.