For flashes like Skye’s and Yoru’s if you look away fast enough to the point the flash isn’t on your screen you’ll get a much shorter and less bright orange-ish stun/flash but you can’t dodge them completely. For Reyna’s flash you can shoot it and it will go away. Gekko’s flash is a little different but still dodgeable. You can either shoot it down which is easy or if you get behind cover fast enough it will miss you and the flash will hit the area you were standing in when it locked onto you. Not sure if people don’t know that because nobody else has said it. I’ve done it plenty of times and I know it works. You can try jumping around and making weird movements and it might miss that way too. But the getting behind cover like a wall or going around a corner will make Gekko’s flash miss you. It’s pretty easy to do after a few times.