hi hi!
Oh the BB's Foundation Stick is more for convenience. It's better if can use concealer. It can be used all over the face or only on some spots that you want to cover.
Of course when i buy concealer, I'll try out the texture. If my eye area is tend to dry, i'll get creamier one.
Actually now, there are some products that can be applied as lipstick and blusher. Last time people also say do not use lipstick as blusher unless it's during emergencies. People say like that can introduce bacteria unnecessary. What i'm trying to say is that as long as we follow what the product is being intended to use, it should be quite safe.
For me, i do have products that can be used as lipstick and blusher. I think technology is such that eye shadow as blusher can be possible one day.
I think why eye shadow is not being used as blusher cos of the color bah. Eye shadow tend to be more shimmery and it'll look weird on cheeks lor. Hehe just some personal view lah...