Matizes translates to "hues" or "shades", referring to different variations of a color. It's a more nuanced and poetic word than simply saying "colors".
In the context of the song, the lyrics state, "Nós, as crianças de muitos matizes" (We, the children of many hues). This beautiful imagery suggests a diversity of people, experiences, and perhaps even emotions, coming together to create a rich and vibrant world filled with peace, love, and invention.