The inside-the-law approach that works to some limited extent is public community rejection. Things like large groups showing up and standing with their back to the Nazis.
The method that has historically stopped Nazis like this involves getting some level of police cooperation and beating them up
Story about the Jewish lawyer who helped the nazis get the right to march:
https://www.newsweek.com/story-jewish-lawyer-who-defended-free-speech-rights-nazis-1771393
Personally, I think it was a mistake but I’m Australian and happy not to have American freedom of speech.
Thanks for showing me this story.