Obscuring faces for privacy, cropping would no longer work. And even minor touchups like lighting would be of questionable value since you're expecting users not to look at the edited photo or at least to primarily look at the edited photo next to the original.

I suspect in practice that doing edits on top of a signed photo would be basically the same as not having editing capability at all; and even that's assuming users would compare the edited and non-edited versions at all, which is not a safe assumption in my mind given how hard it is to even get people to click into a full article past the headline.