Thanks Bart.
its hard to post a clean TIFF example, as jpegs are not fine enough, but here's something. (200% screen grab)
To my mind its Green Chromatic Aberration, but I may be wrong.
I fixed it with a layer mask and color editor adjustment with big -Sat selected, just painted it out with the mask brush. Luckily I can get away with that here. Much rather there was a 'green fringing' slider in C1 though.
Yes, the specific lens profile correction was selected and used. Didn't fix it though.
Phase One 150mm, f3.2, ES on IQ4-150.