Exterior plaster directly with leveling coat?

A leveling coat is applied to even out inconsistencies in the color tone of the plaster. And it is of course also a protection for the plaster. The painter's coat is generally at least two layers, which alone makes the paint last longer (abrasion/washing for mineral paints, for example). The colors are basically similar (with the same base). And the leveling coat should not be applied too quickly either, as there is actually no difference in the open time.

I am facing a similar decision. Do I need this, Egalisationsanstrich, or not?
: How did you decide?