overwatch
When you start a match in Overwatch you can't see enemies' picks. In the middle of the match – you can press Tab and see them.
What happens when some enemy switches hero in the middle of a match? Can I press Tab and see the change immediately? Or does someone on my team need to detect the new hero first? Or do I personally have to see it on the map? When exactly is my Tab-screen updated?
No, there's is not. In fact Jeff Kaplan himself has stated in an interview:
So we we basically stopped displaying any form of scores, kills, deaths because it really wasn't telling the story of who was doing their job properly to win or lose as a team. And really, what it's all about is, "Did you win or lose as a team?" None of that other stuff really matters at the end of the day.
You have some form of knowing if you were one of the top performers of the game by the medals and upvotes you get.
You can also view your performance in the "Tab Menu" or tab-screen. See the next section.
The tab-screen is not the hero select screen. Here's an example of a tab-screen:
As you can see there are some of your stats there that you can check but you can't compare them against any other player. As I've explained in the previous section, this is intentional to promote team play.
During development, Overwatch had indeed a scoreboard that has since been long removed.
The scoreboard used to look like this:
Redditor SpriteGuy_000 has done some extensive testing, and according to his spreadsheet these are the things you can be commended for.
Best Answer
From my own experience, after the time at the beginning of a match where you can't see enemy picks at all, the tab screen shows enemy changes in real time.