I may have found a solution for you. Plugin Pigment.O github / discussion It has more settings. There is HSY’ and, most importantly, there are sliders for HSY’. I could tell about it right away if I remembered it this morning 
Checked it now. I scrolled a hue slider and the lightness does not change. Results in picture.
I don’t use it myself. I want to work in linear gamma(…g10.icc color profiles), but this plugin shows wrong lightness values in that case. Well… Mathematically they are correct. It’s just that 50% gray is not in the middle. And half of slider is just close white. Which is confusing.
I marked the required settings. Play with other panels, maybe you will find something else useful for yourself. Have fun
