Is that possible using the “render to image editor” option?
yes, you just make an image-editor window, then render. The first time you renders, it might render in a random viewport, and not in the one you want. Then, in the image-editor view, there is a drop down menu, in which you can choose ‘Render Result’. When you render, the rendering will be shown in this specific image editor.
I saw that drop down menu but forgot about it.