What do you consider „effective“? This will not change the law. It‘s about raising attention to a stupid law and that happens all of the time. Pastafaris, Birds aren’t real, … are doing the same thing. They confront stupid ideas by exposing them. If it makes a few people think about the issue, if it makes some aware of the problem, then it can be considered effective.
I don't know if it's what the GP meant but I would just be interested in knowing if it's effective in the legal sense, i.e. if a court would rule that it must be displayed despite not being in English.
It looks like it won't work in this case, but other examples of trolling where courts rule in favor of a literal technical interpretation would be funny to see.
I don‘t believe their goal is that a court would rule in their favor, though it would certainly be a great outcome for them. I believe that getting the governments lawyer to make up all sorts of justifications is what they’re aiming for, because that exposes how stupid this law is.
There is a whole trolling campaign which has been extremely effective.
Lots of small towns in rural US say prayers before their town council meetings. The courts have ruled that this is ok, as long as there is no discrimination between religions - any citizen of that town can request to have their own religion's prayers spoken. People in these towns who are opposed to the Christian prayers have declared themselves to be adherents of the Church of Satan, and won court orders giving permission for Satanist prayers to take place.
There are videos of this happening on YouTube. It's, imo, remarkable evidence of something awesome about the American system. The Church of Satan sends someone scary-looking who recites something purporting to be a prayer, but is actually a speech in favor of humanism and tolerance. They are not allowed to make any political statements so they have to disguise it as prayer. They also make sure they get in lots of satanic-sounding stuff as well, to mess with the Christians. The local rednecks look worried and righteous and mumble anti-satanic stuff under their breath. They are allowed to say personal prayers to protect themselves from the devil, but not at a volume which covers up the satanic prayers. There are US Marshalls all over the place in these little town halls ready to jump anyone who violates any of these court instructions. And dozens of lawyers acting like it's an execution and they might be needed for a last minute challenge.
Most towns where this process has started simply get rid of the prayers at the start of the meeting.