Sunn hemp (Crotalaria juncea L.) does not produce cannabinoids like hemp (Cannabis sativa) does and so does not fall under the legal restrictions associated with hemp or marijuana.  They are different species entirely.  Sunn hemp can be treated as any other ornamental plant.

https://edis.ifas.ufl.edu/publication/AG443

https://www.tsln.com/news/sunn-hemp-from-the-tropics-to-wyoming/#:~:text=Sunn%20hemp%20(Crotalaria%20juncea%20l,the%20University%20of%20F(Crotalaria%20juncea%20l,the%20University%20of%20Florida%20Extension.lorida%20Extension.

https://plants.usda.gov/DocumentLibrary/plantguide/pdf/pg_crju.pdf