Technically it’s possible with changing on the FKB Pro theme page the Color Palette to FKB - Dark and the default dark mode color scheme id: FKB - Light. But you shouldn’t do it. This not too user friendly when user change the device to dark mode then it will use the FKB - Light scheme. So I don’t think its a good idea. And the sidebar toggle will also works the opposite way.
If you really want to do this then a little better if you disable the automatic color scheme change site setting. This way the dark/light color scheme change won’t works automatically. But users can select the prefer color schemes on their preferences/interface page.