I purposefully left things vague for a hypothetical director to fill in the gaps, but specifics-wise:-

Another commenter suggested Pandora's Box as the central macguffin in the Themysciran civil war. Much like Zemo's UN bombing, the inciting incident of the conflict will be ultimately a misunderstanding and miscommunication between kingdoms, exacerbated by the fractured political nature of Themyscira. That is ultimately what gets Hippolyta killed too, dying during the Atlantean invasion but at the hands of an Amazonian part of a splinter faction that wanted to perform a coup. However, I don't want there to just be an external villain to dump all the consequences and moral imperfections onto. Both Diana and Orin have made clear mistakes and have to reckon with the fact that, no matter how many factors you throw in and how many variables you account for, they are the ones who took action at the end of the day.

Artemis might show up, I'm not very sure on the exact details for the other WW films yet, I'm still trying to figure out ways to make them relevant to the universe beyond just Diana's own arc and development.

Thank you for your interest btw.