Please see below for the official Injustice 2 Multiplayer Beta FAQ
About Injustice 2:
Build and power up the ultimate version of your favorite DC legends in INJUSTICE 2. With a massive selection of DC Super Heroes and Super-Villains, INJUSTICE 2 allows you to personalize every iconic character with unique and powerful gear. Take control over how your favorite characters look, how they fight, and how they develop across a huge variety of game modes.
Official Injustice 2 Channels:
Injustice 2 Beta FAQ:
Is the beta currently active?
The Injustice 2 Online Multiplayer Beta ended on 2/21/17.
Where can I go to discuss or learn more about the game?
Head over to the official Injustice 2 forums - https://community.wbgames.com/t5/Injustice-2/ct-p/Injustice2