Aizen ended up being confined and his powers were controlled. He was no longer a threat. This conclusion came after a long and intense battle, showing that justice prevailed in the Bleach universe.
One interesting 'Bleach Female Aizen Fanfiction' could be where she has to navigate the complex power structure in Soul Society differently from the male Aizen. Maybe she uses her charm more subtly to gain allies. Another aspect could be how her relationships with other characters, like Ichigo, would change. Since she's female, the dynamic might be more of a mentorship or a different kind of rivalry.
He might become more empathetic. Seeing the past versions of characters he once used or manipulated could make him question his own motives. He could start to value relationships more, rather than just seeing people as pawns in his grand scheme. For example, he might try to protect characters he previously endangered during his time - traveling adventures.
A popular trope in 'Bleach Female Aizen Fanfiction' is the 'Gender - Bending Consequences'. Since she's female instead of male, how does this change the power dynamics in Soul Society? Also, the 'Hidden Agenda' trope is often used. As Aizen, she's always scheming, but as a female, her hidden agenda might be related to issues like gender equality in the spirit world. And there's the 'Outcast' trope, where she's treated differently because she's a female with such great power.