Soundwave's Fate
After getting trapped in the Shadowzone, Soundwave followed all the events that occurred afterwards. The death of his lord and master, the battle against Unicron for the last time, and the revival of Cybertron.
All he could do was watch as the Decepticons were disbanded, the war ended, and the people of Cybertron began to rebuild their devastated planet. He watch as Cybertron rose again in the image that he fought for. Peace and equality among them.
This was the very reason Soundwave had fought in the war. The very reason he had dedicated all his efforts to the Decepticon cause. Soundwave had sacrificed all he had; his home, his time, energy, and his creations all to see his dream of peace in reality.
However, … Soundwave could take no part of it. He was trapped in the Shadowzone. Soundwave could not touch, be seen, or heard by others. He could not help his planet be revived. Soundwave could not live in the paradise he longed for his whole life.
It was very agonizing to just watch and not contribute. To live, but have no purpose. To exist, but not be acknowledged. To see your dream a reality, watching as everyone enjoyed your dream, while you watch it play before you, wishing to be with them.
The longer Soundwave watch his people and planet flourish before him, the more Soundwave was starting to lose himself. Even with Laserbeak there to support him, Soundwave was driving himself crazy. He wanted this so badly, but he knew he wouldn't be able to help.
To prevent further despair, Soundwave had made the decision to abandon Cybertron similar to his former master. He made his way to Earth and watched as the world evolved. The existence of Cybertronians was forgotten as the age of the omnics rose.
Soundwave watched as everything had changed. He watched the beginnings of omnics with souls. Watched as they tried to gain their rights as sentient beings. He watched as the very first Omnic Crisis rose up. Soundwave followed the activity of the early days of Overwatch. Those very days is where Soundwave's fate intertwined with that of Overwatch.