As an experienced player at 11k with multiple 700 brawlers, here is my OPINION (you are free to disagree) on 8-Bit. Honestly, he is pretty balanced thanks to his shit move speed. He will be an OP mid-laner in gem grab, and pretty good in duo showdown thanks to his health, range, and support turret. He will most likely also be alright in heist, but he will probably not be very good in brawl ball, bounty, or solo showdown. IDK how he will fare in siege, but he will also most likely be a good choice, so at least A tier. He will counter tanks pretty well, but will most likely be absolute shit versus long range brawlers or brawlers with a fast movement speed. Dodging with him will be pretty hard, but that's why he has all that health. Some solid counters for him will probably be the throwers, piper, colt, penny, jessie, brock, and maybe rico. Overall, I think he will be at least an A tier brawler, maybe S tier for some game modes.
The best comparison I have for him is probably Pam at her peak, when everyone used her everywhere.