I feel like I should post this in this new thread. This is a post I made from the old Battleborn Beta thread in regards to the differences between Overwatch and Battleborn:
Overwatch:
TTK(time to kill) is much much shorter in Overwatch. A fair amount of characters can one shot other characters.
Modes in Overwatch are very much like Team Fortress 2 modes. There's payload, point capture/defense and king of the hill. I think that's it.
There's no level up mechanic in Overwatch. Every character gets their ultimate by dealing enough damage/waiting a set amount of time.
Respawn timers in Overwatch are generally small. Average FPS respawn timers.
Matches in Overwatch are 6 vs 6, regardless of mode.
You can switch between characters during battle, like in Team Fortress 2.
Overwatch currently has 21 playable characters. More characters may yet be added.
There is no single player component to Overwatch. You can play matches against bots, but there is no story mode.
Overwatch currently has 12 multiplayer maps; 3 per game mode.
Battleborn:
TTK is much longer in Battleborn. Enemy minions die quickly, but the heroes generally don't die very quickly. There's virtually no one shot kills in Battleborn.
Modes in Battleborn are very MOBA like. "Incursion" is a standard "destroy the enemy base" MOBA mode complete with minions. "Meltdown" is a defend and escort the minions to a certain point mode, and there's a point capture mode that seems to have no minions.
There's a level up mechanic in Battleborn, complete with a Heroes of the Storm style talent system. Every level/level up during a match unlocks a new talent. Ultimate skill unlocks at level 5. Maximum level is 10, during battle.
Respawn timers can be long in Battleborn. They're short at first, but at later levels, you stay dead for 60 seconds or more.
Matches in Battleborn are 5 vs 5, regardless of mode.
You are locked to the character you pick during matches, no switching of characters.
Battleborn currently has 25 playable characters. 5 more characters will be added for free in future updates, bringing the total playable roster to 30 characters.
Battleborn has a story mode which can be played single player or co-op in addition to the multiplayer. Each mission generally takes 30-60 minutes to complete, and there are eight of them currently; five more missions are coming via DLC. Players can also play multiplayer modes against bots.
Battleborn currently has 6 multiplayer maps; two per game mode.
There's more differences aside from what is listed here, but those are the major gameplay differences between the two games.