I would send the wildflower seeds even if it is invasive in your area.
Just include that information on your seeds and let the people who get them check and see if they are invasive in their area.
We have one that my mom loves, Sho-Fly, that she kept the seeds from her friends house and babied the plant. We asked for years if anyone knew what the flower was with no luck. Turns out it is invasive in commercial tomato fields in Ohio and on their list. They do "spread like wildflowers" but are easy for a home gardener to dig up and have pretty flowers.
Going to plant some more around the chickens and see if they really are Shoo flies.
I've been doing a lot of research on plants that can act as a repellent to insects, and I believe that was one you could make into a tea (but I don't recall if you used the leaves, flowers or roots) and spray as an effective repellent.