(dieser Post kann leicht mit z.B. deepl übersetzt werden)
To your questions: all of these things are possible in principle.
- header-footer : if the size of the header is constant, this can be achieved via
context. If the header size should change too, you’ll need to have a page break (i.e. content can’t flow from the first to the second page). Flowing content and different margins is more complicated. - text blocks: you would achieve that with functions:
To freely change the inserted text, you’d have to really insert the text, i.e. copy/paste, or a snippet function of your editor of choice.#let greeting(name) = [Dear #name,] #greeting[Norbert] - I don’t think a German handbook is on the horizon, see e.g. here for discussion: Will website & docs support community multi-language?
In case you were just looking to identify possible show-stoppers, I hope this is sufficient. If you need more help, let us know.