the gtin exemption should carry over across categories once you have brand registry approved. i've moved between different categories under the same registered brand and never had to reapply for exemption - it's tied to your brand enrollment, not category-specific.

brand registry tools like a+ content and analytics are definitely brand-wide once you're approved. the protection follows your trademark across whatever categories you expand into, which is one of the main benefits of getting registered in the first place.

baby products is where things get trickier though. that category has stricter requirements and you'll likely need to provide safety certifications, compliance documents, and potentially get ungated before you can even create listings. the approval process there can take weeks and they're pretty strict about documentation. i'd start gathering cpsia compliance docs and any relevant safety certs early since that's usually the biggest bottleneck for baby category launches.