I used to use Dropover or yoink as a temporary place to save images, I will drag and drop to the other place like another folder or website, then the temporary images will be deleted just like move files.
Can KM do that?
I think that the starting point for such a macro would be the as described in the Wiki under “How do I insert styled/colored text or images?”.
However, if you wanted your macro to behave just like Dropover or Yoink, you would have a lot of work ahead of you to imperfectly reproduce the functionality that those applications already give you.