When imagining the story from Katrina's perspective, the most important point to bear in mind is that Irving's Katrina is the epitome of a flat character. We know nothing about her thoughts and feelings. This may well render the task easier, since you have carte blanche to decide on her point of view, so long as it is consistent with the events of the story.

All we know about Katrina is that she is a very pretty girl with a wealthy father. This makes her the cynosure of all eyes, with Ichabod Crane and Brom Bones Van Brunt both coveting her hand in marriage. She rejects Ichabod and finally marries Brom Bones. A narrative from Katrina's point of view should first establish how she feels about Ichabod. Does she know how he feels about her? Does she encourage him in any way? Does she, perhaps, feel sorry for him, or is she merely being polite? You should also consider how she feels about Brom Bones and why she marries him. Does she love him? Is he the best option available in Sleepy Hollow? Could there be another reason?

The story narrated by Katrina would be very different, from beginning to end. If Brom Bones tells her about his prank to frighten Ichabod (assuming that this is what happened), then we might include that story at second hand. Otherwise, it would be lost entirely. Indeed, the story from Katrina's perspective might be a rather simple and conventional romance of rival suitors, ending with her marriage to Brom Bones. Ichabod would play a much more minor role in such a story than he does in Irving's.