You can do that now with the latest ICUE:
https://i.imgur.com/wJxgeio.png
I have Corsair Link Logo printed on it too :)
https://i.imgur.com/wbhIGeE.jpg
It is outdated, but can still fit in the RGB ecosytem. As you can see I can customize the color of the h100i pump thru corsair link.
https://i.imgur.com/WS9xDAC.jpg
Still hoping for support for my old H100i (still working from 2013.) I just don't want to use a separate Corsair Link software just to control the fans.