Plot[{Callout[Sin[x], Sin[x], 5,
   LabelStyle -> Directive[ColorData[97, 1]],
   CalloutMarker -> "Circle"],
  Callout[Cos[x], Cos[x], 5.5,
   LabelStyle -> Directive[ColorData[97, 2]],
   CalloutMarker -> "Circle"]}, {x, 0, 2 [Pi]},
 GridLines -> Automatic, PlotRangeClipping -> False,
 PlotRangePadding -> {{0, 0}, {0.1, 0.1}}]

Short[ColorData[n, "ColorList"], 4]