Summary
Echo is a playable character in Blizzard's 2016 video game, Overwatch. She was added in mid 2020, and was the 32nd character added to the roster. I actually bought the game with a friend the same week that she was released, so I didn't really experience the release hype that other fans experienced. That month, though, every game had two Echoes (one on each team), if I queued for DPS I had to select the character as fast as I could or the other DPS would get her.
Lore
I really like Echo conceptually; she is an adaptive robot (sapient robots are known as "Omnics" in the Overwatch universe), and was developed by Overwatch researcher Dr. Mina Liao. Liao spent all her time in the lab with Echo, and Echo's personality is based on Liao's, because she imprinted onto the developing Echo. Her development was kept strictly secret, with only a handful of people knowing of her existence, Blackwatch agent Jesse Mcree being one of them. I believe Mcree canonically spent a lot of time with Echo, though I don't remember the circumstances. Liao created the Omnics in general; she created the Omnic race before Null Sector became a thing. Echo was her crowning achievement, the most powerful of all the omnics. Overwatch deemed Echo to be too dangerous, and eventually ordered that she be put in stasis. When Reyes (Reaper as known in-game) betrayed Morrison (Soldier 76 in-game), the Overwatch headquarters were destroyed and Mina Liao was killed in the process. This led to the destruction of Overwatch in general; it fell apart.
Many years after Overwatch had disbanded, Winston decides to illegally recall Overwatch. (Which really seems like a bad idea without commander Morrison because he was like the head hancho and I have doubt in Winston's administrative capacity, him being a gorilla and all) Jesse Mcree was working as a mercenary. He knew that Echo would be hauled as cargo on a specific train, and anonymously tipped off the Deadlock Gang (which he used to be a part of), who blew up and derailed the train so that they could loot weapons from the cargo. He said that all he wanted was Echo's stasis chamber (I think he just referred to it as "that box"), and Ashe (the leader of the Deadlock Gang) could have the rest. Ashe, unwilling to give up something valuable, refused, and they had to have a "confrontation". Mcree John-Wicked his way through the confrontation because he's a bona-fide badass I guess and everyone misses their shots but him, and then he awakens Echo and basically prompts her to heed the Overwatch recall.
The casual intimate familiarity and friendship that Echo and Mcree share in the cinematic just, ughhhh I love it so much. Their target demographic is like teenagers but I still really like it okay? The characters personalities are really well done and their quirks are super lovable.
I still don't get why Echo has her own cinematic but Tracer doesn't, when Tracer's the poster-boy (or covergirl?) of the video game, but it's whatever. At least she's in a cinematic.
In-game abilities
There are three character classes: Tank, Damage, and support. Echo looks like a support character, but she's a damage character. Her primary fire is a triple-shot, in which she release three projectiles in a tight triangle formation. Her secondary is sticky bombs, in which she release three sticky bombs, not in a triangle formation. The special attack is a "focusing beam", which does minimal damage normally but mows down characters if their HP is under half. And, last but not least, her special ability lets her fly way up into the air and then slowly glide back down if you hold space. This makes her highly maneuverable, able to fly up above the battlefield and scope people out. Her shots travel in a straight line and do not sink with gravity, so you have to be very precise with your tracking. Also, because you glide slowly to the ground, you're an easy target for snipers like Ashe or Widowmaker. Her ultimate ability is perhaps the most unique in the game; you get to "become" another character for 15 seconds, and you acquire that character's ultimate. That character's ultimate will charge obscenely fast, so if you get some good hits in you can use it a couple of times before your ult wears off.
I can't play Echo. I'm terrible on Echo. I can never seem to land shots on an enemy Echo, but when I play echo I just get mowed down by snipers every time I try to fly up in the air. Also, landing shots is so difficult because her shots are so precise.
Links
The Reunion cinematic, where Mcree frees Echo.
The character introduction cinematic, in which the addition of Echo was announced. Not really a cinematic though.
A cinematic-gameplay crossover of sorts in which it showcases Echo's gameplay style