Violet Haze by C. E. Kilgore

Caleb finds himself evolving beyond the boundaries he was programmed with as the planet Corwint struggles to find stability during the Mechatronic Automaton rights movement. Meeting Violet, a rare female Mecha, encourages him to follow the evolution to its fullest potential, while violent events surrounding the rights movement pushes them both to stand up for acknowledgment of their existence and their right to live equally.

This is side story to the main series.