Hi, Edge mode is a feature that works at render time, removing elements which are outside of the scatter area. Therefore, it requires to implement a custom shader with certain capabilities, but actually only V-Ray allows that.
For other renderers, we have implemented an interface which can be used by the developers of these engines, to write its own shader. But since each render engine and company is different, that such feature is finally implemented will depend of them.
Sincerely, i doubt that Edge mode would be implemented in Octane, because our interface runs in CPU and cannot be executed from GPU engines. Anyway, we have sent the documentation to the Otoy team.