Secunda color

I think pink is very beautiful because Segunda is not 100% like Prima because she is mutated

I voted yellow as it gives her a warmer color contrast to prima like when she was metallic brown in the original comic.

Yellow.

I think blue is more icy, robotic and harmonious. And the silver body paired with warm RGB lights is a bit strange.

I don't perceive any problems with the current color scheme; however, if you're considering any change, a gold hue could be a good choice. While my personal preference is pink, I'm hesitant to suggest it since pink and blue are often used stereotypically to distinguish between genders. Given that the comic revolves around the characters Miller and June transforming into Mercury and Secunda, both of whom are girls, I find such gendered color associations controversial because its almost like a reminder of their prior gender. Therefore, a more neutral or unconventional color palette might be preferable.

Definitely yellow for me.

Pink would play the nicest with Primas blue

Given that the pre-remastered version of June was supposedly "iron"-based, how about more of a rust-red color?

She need pink because pink eyes scream mind control to me.

By RGB light, do you mean her stripes too?

So I think pink might be the right direction color wise. Though personally I would definitely go for something more like the color rose.

Green would be cool