More progress with my experiments with style changing from a basic Poser real-time render. Up the CFG to 9, up the Embedding strength to 1.2, up the Img2Img Denoising to 7. Keep Canny at 87%. Specify dotted_line in negative, and change Steps to 42, with together remove some of the granulation of the lines that would otherwise occur.
Apart from the thumbs and a stray line below the buttons, the layer registration with the original is exact. Meaning easy re-colouring in Photoshop, via a normal Poser render and the ‘Color’ layer blending-mode.
The face is now too chiselled, and a H.P. Lovecraft character LoRA may be called for. But worth the extra work, since the eyes now especially benefit. There is a slight painterly smudge on the white, which you may be able to see here on a good monitor. But the original outline should be able to be selected in Photoshop. If not, one could use a mask from Poser. Or just do the scene with a backdrop straight from Poser.
The subtle 3D shading being auto-added could interfere with any light-direction shading you wanted to add later (perhaps by dropping a Smooth Shaded Poser render into the layer stack, in Photoshop).