So it has been recently announced that the Evelyn Sharp character introduced in Arrow Season 4's "Canary Cry" who took up the mantle of the Black Canary after Laurel's death will return in Season 5 but now as Artemis.
What I think this could mean for the Arrowverse going forward is another spin-off series centering on the Young Justice team made famous in the animated series of the same name. Why do I think this? This is the reason for this post.
1. Kid Flash Has Already Been Introduced
So while we still haven't seen Wally West take on the mantle of Kid Flash, we know from this promotional imagery that he will somehow become a speedster in Season 3 of The Flash. In the Young Justice series, Kid Flash and Artemis were in a relationship which was one of the high points of the series for me, whether or not they'll do that with Wally and Evelyn remains to be seen particularly as Wally seemed to be getting close to Jesse towards the end of Season 2 and she is scheduled to be returning for Season 3 also. Regardless with Artemis coming in we now how two of the original members of the team already in play.
2. Supergirl Seems To Be Setting Up The Pilot Three-Parter
With Project Cadmus being strongly alluded to ahead of the second season, it stands to reason that because everything to do with Superman seems to be handled on that show that we see Superboy make an appearance, made more valid by the fact Guardian will also be introduced in Season 2.
Also Martian Manhunter has proven very popular on that show, for that reason they could choose to bring in Miss Martian to develop him further. While the show is set on a different universe (Earth-4), there's no reason why they can't crossover with Earth-1 especially now they're all part of the same family.
3. Aquaman Has Strongly Been Alluded To Already
The Flash season 2 has made two references to Atlantis and by extension Aquaman existing on Earth-2. Now if we have Kid Flash & Artemis on Earth-1 and Miss Martian and Superboy on Earth-4...it makes sense we have Aqualad on Earth-2.