I really love the idea of domain driven design, however, as I'm learning Go, I'm wondering if there's the equivalent of DDD that's aimed at an effectively more functional language?
There's no equivalent. DDD needed a paradigm to support frequent rewriting in an evolutionary software development scenario. OOP looked like the only viable strategy back then. But Functional languages can serve such a scenario as well.
I believe DDD is not about OOP design itself, but more about how you approach the whole development process. Iterative development, ubiquitous language, close cooperation of business experts and developers are all language and paradigm agnostic.
Design of objects in DDD is not something new. The patterns that are described in DDD existed long before DDD saw light of the world. Agregate roots, strategy pattern, value objects were only good fit for describing the business logic. So your question should be more like "How to express business logic and persists it's state in functional language". You are probably looking in design patterns for functional programming languages.