various questions -

1) I'm am wondering - are there translucent colored body paints that tint the skin (not stain it)?

I've used Mehron, Kryolan, Tag brands, but they are all opaque. so, to give an example of the effect I am looking for - nipples are darker than regular skin. if you apply an opaque body paint to the chest, the nipples and surrounding area will look the same shade. what I want to achieve is an overall blue, red, green, etc. but retain the shade difference that we see in nature. I suppose the same effect can be achieved in post, but I prefer to get the effect before that.

2) I've used Mehron silver powder with olive oil (great effect) I'm curious about using other pigments with food oils - reds, ochres, browns, blacks, black light reactives. I know cosmetic grade pigments are used to color soap.

is there a good reliable source for cosmetic grade pigments that ships internationally?

3) what is your 'go-to' brand for interference or shiny body paint.

Have you tried just thinning out whatever paints you use? Or, maybe adding them sparingly to some sort of clear base?

I'd be interested to see what the results might be, and also to try out some of the paints you've mentioned.

search for "cosmetic mica powder".  I would call the seller/manufacturer and ask them if they are fd&c approved.  I don't know anything about this company: wwwDOTmadmicasDOTcom, but they seem legit and I would check them out.  Just use a lot less for translucent effect.  personally, I swear by Mehron, but you're right, they are usually pretty opaque.

thanks for the link, the Dyes & Lakes seem like they could solve the translucent issue, and I am interested in their Neon colors.

I have had some success tinting skin my mixing powdered makeup with baby oil. Careful of the streaking. I find that showeing and tower drying will moisturize the skin enough that the oil/pigment solution stays on top of the skin rather then getting absorbed.

Most translucent body painting makeup is black light reactive. European Body Art albeit airbrush does have some more translucent makeup and has and additive to make their makeups such. As for classic brush Kryolan also has an excellent translucent line in metal is and duo chrome colors.  The are several ways to paint aka tint skin in a translucent look but many mean your model will be stained hence I recommend makeup. As for the makeup aka body paint brands you note all can be reduced to a wash making them more translucent.