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. ...