Handpainted braids are beautiful, and they can be a lot of fun to spin (painted braids look something like these ones on Etsy*).
How does the act of spinning affect the colors in the braid? A lot of it depends on how heavy you spin, whether you spin worsted or woolen (or in between, like me), the weight of your single, and how you split your braid. All in all, the answer is: sample your braid and see.
However, the way that you choose to ply your singles will affect the way that colors will play out from a braid. Different plying techniques will change the way that the colors interact with each other.
The yarns presented below were all from the same braid. The cable ply was spun first, the two ply was left over from the cable ply, and the chain ply was the left over singles from the first two projects. The cable ply is roughly worsted weight, the 3 ply DK/sport, and I’m estimating the 2 ply fingering/lace. The fiber is BFL.
*I have no association with the store other than liking the braids.