JLA Adventures: Trapped in Time (2014) on Netflix

Plot summary

Lex Luthor's Legion of Doom fires cryogenic rays from orbiting satellites to expand the polar ice caps, lower the seas and raise new islands for the Legion to rule. The Justice League destroys the satellites, and Captain Cold overloads the last one, which falls and freezes Luthor. A thousand years later, the teenage trainees Dawnstar and Karate Kid are touring a museum of the League's exploits when they loose Luthor from his suspended animation. He studies the exhibits, learns Superman's secret identity and takes the Eternity Glass, an artifact that commands the Time Trapper. Holding that power, he travels back to the present to lead the Legion again, with the two young heroes following.