Question: what are the arrowverse crossovers?
Answer: Crisis On Infinite Earths (2019/2020) Crisis On Earth-X (2017) ...  World's Finest (2016) ...  Duet (2017) ...  Invasion! ...  Elseworlds (2018) ...  Flash Vs. Arrow (2014) ...  Heroes Join Forces (2015) Heroes Join Forces was what the two-part crossover in the 8th episodes of The Flash season 2 and Arrow season 4 was dubbed. ...