Gist for the delay plot

plot.py

# df_delay = Pandas dataframe with data

ax = df_delay.plot.scatter(
    title='Symptom Onset vs Confirmation - COVID19 / Rio Grande do Sul / Brazil',
    x='DATA_CONFIRMACAO',
    y='DATA_SINTOMAS',
    alpha=.4,
    lw=0,
    s=8,
    c="Delay (days)",
    colormap="Reds_r",
    figsize=(7, 5), sharex=False)

for axis in [ax.xaxis, ax.yaxis]:
    formatter = mdates.DateFormatter('%d/%m')
    locator = mdates.WeekdayLocator(interval=1)
    axis.set_major_formatter(formatter)
    axis.set_major_locator(locator)
    
for label in ax.get_xticklabels():
    label.set_ha("right")
    label.set_rotation(45)

plt.grid(alpha=0.4, zorder=-1000, linestyle=":")

plt.ylabel("Symptom Onset Date")    
plt.xlabel("Confirmation Date")

plt.tight_layout()
plt.show()