Yes, there are many. Some fanfictions might explore the relationship between Alex's sister and other characters in the 'Orange Is the New Black' universe. They could add new storylines, like how she gets involved in the prison world in some way or her interactions with the inmates' families.
We can expect new relationships to be explored. Maybe Alex's sister forms an unlikely friendship with an inmate. It could also show her perspective on the prison system and how it affects those around her.
Explore her relationships outside of Alex. How does she interact with her parents? Does she have a love interest? These relationships can add depth to her character. If she has a love interest who is against her getting involved with Alex's prison - related issues, it creates a conflict. Also, showing how she copes with the stress of having a sister in prison, like through art or exercise, can further develop her character.
One possible plotline could be that Alex's sister gets involved in trying to clear Alex's name. Maybe she starts her own investigation into the events that got Alex into prison. She could meet some of Alex's former associates, both the good and the bad, and face various challenges and threats along the way.
Self - discovery is a theme that pops up as well. Both Piper and Alex are on a journey of self - discovery in the series, and fanfiction writers like to expand on this. They might write about how Piper discovers her true self through her relationship with Alex, or how Alex overcomes her past traumas and becomes a better person because of Piper. It's interesting to see how the relationship is used as a tool for their personal growth in these stories.
One great place to find Orange Is the New Black Piper and Alex fanfiction is Archive of Our Own (AO3). There are many well - written stories there. Some fanfictions focus on their relationship in prison, exploring how they support and challenge each other. Others might be set in an alternate universe where they meet under different circumstances, like in a college setting or a normal workplace, which gives a whole new perspective on their dynamic.
Redemption is also a theme. Given Alex's past and her time in prison, many fanfictions explore her journey towards redemption, how she tries to make amends for her actions, and how other characters react to her attempts.
Maybe a plot where they have to work together to solve a mystery within the prison walls. There could be a series of strange events happening, and they are the only ones who seem to notice. As they dig deeper, they discover secrets about the prison's past and end up strengthening their bond in the process.
In fanfiction, their characters can be developed more freely. For example, Alex could be shown to have a softer side earlier on compared to the show. Maybe she shows more vulnerability when it comes to her feelings for Piper. In the show, it took a while for that to surface fully.