After several years of saving Star City and fighting alongside other heroes to protect the world, Arrow lost his life in the Arrowverse crossover event. Oliver returned as the Specter and was killed again in a dramatic confrontation with the Anti-Monitor.
Of course, this idea of resurrecting Oliver for a ninth season of Arrow is unlikely to come true, but it has led to a lot of talk about how it would work. This is what Arrow season 9 could be about.
Oliver Queen from another era
One way to use time travel is to combine Arrow season 9 with its Green Arrow and the Canaries concept. If the show is not picked up on The CW, the idea behind the show could be recycled into season 9 of Arrow.
With Oliver Queen, Arrow, traveling back in time to 2040, where he could form an alliance with his daughter, Mia. This would allow the show to give Oliver a completely different cast and supporting direction.
Oliver Queen as Specter
If Oliver returns, he could be like the Specter and not like the Arrow. After all, Marc Guggenheim said when he was still overseeing the Arrowverse, that “the goal” of making it the Specter was to create new opportunities.
This certainly leaves the impression that the writers already have a plan in place should Amell return to the Arrowverse. Ultimately, Oliver returns as the Wraith feels like the scenario more likely than Arrow.