It's in the Stars (It's been Written in the Scars/On our Hearts) (фемслэш)

Kara Danvers was still getting used to her dual identity: CatCo reporter by day, Supergirl by night—or, you know, whenever disaster (or hostile aliens) decided to strike. When Lena Luthor showed up in National City claiming she wanted to transform her notoriously anti-alien family’s company into a “force for good,” Kara wasn’t sure what to believe. Was Lena really as different from her Super-hating brother and mother as she seemed? And why was it that Kara couldn’t seem to stop thinking about her lovely—er, her brilliant—about her?
When she’d moved her father’s company to National City, Lena had hoped to turn over a new leaf both for the embattled corporation and for the Luthor name. But with first Lex sending his goons after her and now their mother doing a convincing stint as the devil incarnate, those plans had flown out the window. At this point, Lena was just trying to weather the latest assault and survive a potential coup by L Corp’s board—oh, and deal with the highly inconvenient crush she had somehow managed to develop on Superman’s cousin.
AKA, slow burn post-Medusa Supercorp with a side of Sanvers. There Will Be Angst but also There Will Be A Happy Ending, Damn It.