The Flash can never use his powers again as after the defeat of Superman and his regime, heroes are facing consequences for their actions. As Superman is being held in a red sun prison, Wonder Woman is imprisoned in Themes and the Green Lantern has been turned into the Guardians and enslaved. However, the Flash avoided a brutal fate by refusing to side with Superman.
But now he's under house arrest and prohibited from ever using his powers again. Basically grounded, Barry arrives at the longest road in Australia, a place he saw as paradise, as he could run all day and just think. But now all he could do is just think as he has a hard time walking as a normal person, seeing it as agony.
Suddenly Barry witnesses a truck about to crash in front of him and knows that Batman is watching him, but he is the Flash and he can't stand still while someone dies. He uses his speed and instinctively saves the driver from the minor crash. Suddenly, his ankle monitor starts beeping and Batman tells him he's watching him and that they had an agreement, but Barry says he can't just stand by and watch someone die.
Bruce thinks for a second and tells Barry to stay out of trouble and not use his powers. After walking for what seemed like hours, Barry reaches his destination and finds an old friend named Mitchell, who went by the name Galaxor, but is now paralyzed and living in his mom's basement after he tried standing up to Superman and Wonder Woman, but they beat him up and blew his back out while Flash stood still and watched, knowing he could have saved him like me when I watch my dad beat my little brother. Mitchell asks Barry who he is, and Barry reveals he was the Flash and praises Mitchell for standing up to the tyrants.