plt.plot(x, [y_i-1 for y_i in y], color="r") plt.plot(x, [y_i-2 for y_i in y], color="#FF5733") plt.plot(x, [y_i-3 for y_i in y], color=(0, 1, 0)) ...
When setting a color in rcParams for lines.markeredgecolor this color is used for the errorbar caps when plotting with errorbar. No option is able to override this color again.