https://koreader.rocks/user_guide/
This is for a start
Margins and in bottom menu. There is an option to sync L/R margins.
Hyphenation is controlled in top menu. There are algorithmic hyphenation or by hyphenation dictionary. You can also switch it off.
Contrast and sharpness indeed go hand in hand, but this is more about “boldness” (thickness of curvatures along the main character font lines), while sharpness comes as a side effect of tweaking it.