Building a retaining wall in the garden: formwork stones or L-stones?

B has already built, but probably without taking A's ideas into account, because A had no time or desire to talk to B beforehand.

When I read the TE's older posts, the house has already been standing for about 2 years. Was there anything about terrain modeling in the building application?

Since the TE is not responding, it's all speculation.

Since the OP does not respond, it is all speculation.

The OP will be annoyed about this and feel mocked that his from his point of view simple question is taken seriously and answered sensibly, for which in our completely inexplicable opinion clearly presented facts would be useful. So let's not torment him any longer and finally give him the desired answer: 42.

What did he pay for that? What kind of wall did he build? How did he prepare the ground? What did he pay for it? Which federal state?

That's not what this is about here. . Do you notice anything?