Hi. I thought of this idea randomly and I think it'd be super handy, although I'm not sure if it exists already.
A client-side mod that allows you to add a word to a filter, and checks the message you're about to send in chat- if it contains that word, it's removed from the sentence and the rest of the message is sent, without the word. This would be useful for servers where cursing is not allowed, and can even earn you a ban. It's not like you're bypassing 'being punished' either, since the word is removed before it is sent to the server, it's like you never typed it.
If that is too complicated, then just not sending the message at all when it finds a filtered word, would also be equally as good!