i don't have french violet, so i can't really say anything about it. but on the other ones;;
*kelly green makes a great bright green and has great texture and sticks well to bases.
*deep blue green is really dark and would make a great liner or crease color. sometimes it can fall off while applying.
*emerald green is a very beautiful color. it doesn't stick as well as some of the other pigments and some of it tends to fall off while applying. but it's still one of my favorites.
*clear sky blue is somewhat difficult to work with. it's a little harder to blend in other things since it's a matte and also the texture can be chalky. but the color is like none other and is really beautiful.
of course this is all IMO, but i hope i helped a little! :]