Had this idea recently. This isn't a personal headcanon, it's more of an AU thing.
I don't own Overwatch. And I haven't read 'London Calling' so Emily's personality is from fics and fancomics.
World of Orange
...
Lena Oxton sat in the waiting room outside her friend Angela's office. She was there for her annual checkup (which she found to be a bore) and was passing the time by reading an old detective novel from 2016 by the name of The perplexing theft of the jewel in the crown.
She was getting to a good part when she was called in. Reluctantly, she put the book down.
Angela sat her down, a grave look on her face. Lena's heart plummeted upon seeing that face - she had seen it quite a few times on the battlefield, and it never boded well.
After a few agonising moments, Angela sighed "Tracer, have your eyes been causing you pain in the past few months?"
"Yeah. My vision's been a bit blurry too - I probably need glasses." Tracer replied with a shrug.
Mercy bit her lip.
Tracer's frowned "What's up Love?"
"I'm sorry Lena..." Angela leapt over and half-crushed Tracer in a hug "I'm so sorry..."
...
Turns out Tracer had a rare eye disease of some sort. She couldn't be bothered to remember the name, but she knew one thing - it was in the advanced stages.
Over the next three months, she squinted when she tried to read Murder at the Grand Raj palace. She struggled to read the menu at Kings Row's local coffee shop. She nearly died when she didn't notice a STOP sign and crashed into another car.
Then it happened.
...
Clak. Clak. Clak.
Tracer's cast made it's routine clak against the gravel pavement as they took a walk around regent's park. The emerald grass was being brushed by the shining sun as they passed wrinkle-canyoned old men, bright-eyed little children and couples of all shapes and sizes holding hands (and snogging).
It was a beautiful sight.
Emily looked at Tracer, who was wearing a pair of black sunglasses she had bought two moths ago and refused to take off "Lovely day, isn' it?" she asked, her Irish Accent particularly nice on this fine day.
Without looking at her, Tracer smiled "Yeah. I-" she paused "Sh*t."
"Lena?"
Slowly, Tracer took off her glasses. Then she looked at the love of her life, her eyes flooding with tears.
With a shaking voice and and many sobs, she told her.
She had been going blind for months, and the slow, terrifying process had finally finished.
"I- I- I- I didn't want to worry you." she sniffed as they sat on a bench "Now I'll never see King's Row again. I'll never be able to look on your face again! Or any of my friends! And- and-!"
Emily shushed her as she held her girlfriend closer, gentle as a mouse "It's okay, it's okay..."
...
It's a common misconception that being blind means eternal darkness. As a matter of fact, the majority of blind people have light and shadow perception. Not tracer. She was the kind of blind person who didn't see anything at all. Not darkness, not light, nothing.
All she had was her other senses.
While she was angry Tracer lied to her, Emily's primary concern was learning how they could both deal with this.
" So... did the doctor give you something that tells you how to del wit' being blind?"
"Yeah but..." Lena blushed "I threw it away."
Emily sighed "Good thing we have the magic of the internet with us."
...
Over time, Tracer got used to being blind.
She was still allowed to visit the Overwatch headquarters and was kept on as a consultant. It wasn't the same, but it was the nearest she could get to it.
Oddly, Winston had been too busy to see her. He had shut himself in his lab, hanging a 'KEEP OUT' sign on the door. At one point, Tracer asked Ziegler and Mei to go and talk to him, but they came out telling her he had a surprise for her.
What kind of surprise was it? The technology to cure blindness had been banned 45 years ago by idiot politicians. What could Winston do?
One day, Winston paid the pair a visit. It was a bit of a bizarre sight seeing the gorilla wearing an enormous hoodie and pair of joggers, but he had a big grin on his face (or so Tracer was told).
"Put these on, Tracer." he said, placing something in Tracer's hands.
She felt the object. It was a pair of glasses. They were a large pair with rounded lenses.
Sighing, she took off her own glasses and put them on.
Then she gasped.
She saw Emily, she saw Winston, and she saw the room. All in a world of orange.
"Wha- how-"
Emily stared, slowly putting the pieces together "Are you...?"
Tracer had no words. She threw herself against Winston and wrapped her arms around him.
Yes, she was in a world of orange.
But Winston said that these glasses were just a prototype, and that Tracer would be the first of millions to receive the final product.
Even if he couldn't find a way to, she was happy to see again, even if she was in a world of orange.
...
This is just a dumb idea I had recently. I'm not going into the science of the glasses.
Also, The perplexing theft of the jewel in the crown is an actual book by British author Vaseem Khan! I really recommend the series it's part of.
Favourite and review!