Plotting two shapefiles in same plot. Legend of 1st shapefile hidden by second shapefile. Python GeoPandas

With

ax = gdf.plot(cmap="jet", column=ColumnaAVisualizar, categorical=True,figsize=(12,12),legend=True)
ax2=ZDE.boundary.plot(ls="--",color="k", label="Zona de Estudio", ax=ax)
plt.show()

It gives:

Now with

ax = gdf.plot(cmap="jet", column=ColumnaAVisualizar, categorical=True,figsize=(12,12),legend=True)
l1=ax.legend(loc='center right', bbox_to_anchor=(1.0, 0.5))
ax2=ZDE.boundary.plot(ls="--",color="k", label="Zona de Estudio", ax=ax)
l2=ax2.legend(loc='center left', bbox_to_anchor=(1.0, 0.5))
ax.add_artist(l1)
plt.show()

It gives:

So I would like something with the two legends:

PS: Both gdf have the same CRS.