Insulation is visible on the facade

Hello Ladies and Gentlemen,

On the facade of our house, the "pattern" of the insulation panels has become increasingly visible over the past few months. The plaster is not dirty; rather, the insulation seems to be shining through. It really looks strange and is somewhat difficult to describe.
The house was built in 1980 and consists of 36.5 cm pumice masonry, above which there is a 5 cm thick styrofoam insulation, a reinforcement layer, and finally the mineral plaster.
There are two special features: I painted the facade with a Lotusan paint and during the winter, the house remains empty for several months and is only heated minimally.
Given these conditions: What could be the reason that the outlines are visible on the insulation, and what can I do about it? Thank you for any information!

What is becoming visible are the joints of the insulation boards; the joints have a higher thermal transmittance value than the insulation boards, there is a thermal bridge at these points, condensation occurs, dust, pollen, etc. settle here and appear as joint patterns. It has nothing to do with the Lotusan paint. There is little you can do about it; the visible joint pattern often occurs in houses from the 80s. At that time, the joints were closed with mortar, today this is done with (spray) insulation material. Applying a second insulation layer would be elaborate but effective. Otherwise, you have no way to get the problem under control permanently.

A new coat of paint would not eliminate the cause, but if the result would last for a few years, it would definitely be worth it to me. Can one make a prediction as to how long it will take before the pattern of the joints reappears on a newly painted facade?

A coat of paint has nothing to do with the problem; it would only temporarily cover up the problem; unfortunately, no prognosis can be given as to how long that will last.