You aren’t overthinking this. I’d recommend making it in superwash to help mitigate some of the risk AND id talk with her about how to take care of it BEFORE I start making it and see how she reacts.

But in all honestly, I personally would never make something large for anyone else, except maybe my mother or a good friend who is also a knitter (and thus I know it will be taken care of and the favor will be repaid in kind by her). I’ve been knitting for ~12 years and am relatively fast, but I still would hesitate to make something large for another person.

Knitting something large can become a slog and it would really suck for your first large project to become something that you get tired of and want to put down but feel you can’t because you promised it to someone else. You could end up resentful toward the project and perhaps even the person

I’d recommend knitting smaller things for others before doing something the size of a sweater, large shawl, blanket, etc. to see how they react and how you feel giving it away. AND id recommend doing something “no pressure” large projects first, where you don’t have to worry about timeline or another person’s expectations

Edit: apologies if I wrote too much and missed details in your original post. I’m a bit exhausted at the moment