However, you could consider these options:
* "Shout out" - This phrase means to publicly acknowledge or express gratitude for someone. While not a perfect homophone, it has a similar sound and could be used in some contexts.
* "Shout" - While "shout" itself doesn't mean "shout loud", it implies a loud utterance. You could use it if the context makes it clear that a loud shout is implied.
Remember, the best way to convey the meaning of "shout loud" is to use clear and concise language.