You can certainly import an image of a brace, yes. I suggest you prepare an SVG of the brace using an application like Illustrator, Affinity Designer, or Inkscape, and then import that using a graphics frame. Using an SVG will guarantee that it looks good at any resolution.
Well, I’m a student and a composition professor required me to adjust my orchestral score like that. He required me to use braces to group each instrument, for instance, Horn 1,2 and Horn 3,4, Vln I and Vln II, and use the bracket to group strings division. Before I meet him I was using the brackets for everything except piano and harp. I can’t judge whether it is correct, but he is a professor and I am not. So I’d rather be modest and learn whatever is new for me.
We generally avoid these sorts of “why would you do it like that” answers, but in this case it’s valid to point out that the bracketing you want is indeed not typical, which is why it’s not natively supported. I’ve never seen it in a score.
Yes, you are right, it is not typical, because the music is not typically traditional, and it supposed to use an extended technique notation if possible. I’m using a lot of different rhythms in each division. If I write them into one staff it will be a mess, and if I use an extended technique notation it will slower the rehearsals, according to the professor. So instead of attaching a long explanation on the score, I’d rather notate it as traditional as I could, then the orchestra can read it effectively. I think a lot of untypical things are possible in contemporary classical music personally, especially for orchestral music.
I won’t be able to offer more details, because I don’t like to show my score anywhere in public before I finish it, sorry.
Nobody’s saying that divisi strings are atypical - they’re perfectly standard. It’s not modern practice to use a curly bracket to join multiple instruments, though.
I agree with you. I used to use the brackets for morden music too, and my attitude is to do whatever the professor tells me when I’m still a student. If it is incorrect, then I will adjust it after graduating.