There’s probably a rather boring technical answer to this. I’\m not going into that. I can only tell you as an Englishman with many years of architectural drawing behind me what I think.
We generally call the person who does the technical drawing a draftsman, not a drawingsman (no such word AFAIK). But we call his output drawings not drafts. We tend to use the noun draft in this context to mean version. So you do the first draft of a drawing, for example, before it is amended and becomes definitive.
I guess the word drafting does exist but it is not in common use.
And your English is much, much better than my German!