Negative Lab Pro would be a good option, but it works with Lightoom Classic only.
The basic way to eliminate the orange cast is to white balance it (with the eyedropper over an unexposed area) and then invert the image. I don't know about ON1, but if it does not have an invert function, you can do it with a curve by dragging the left side all the way up and the right side all the way down.
Note that after inverting some controls will have the opposite effect. For example, if you increase exposure, the image will get darker.