DynamoDB Transactional Write on Global Tables With DB Streams

Question

How does DynamoDB handle TransactionalWrite on the same item in a Global Table over different regions?
Example scenario: I have a global table in the us-east-1 (N.Virginia) and us-east-2 (Ohio) regions. I have distributed system which does a transactional write operation on an item. There can be a scenario where the same transaction write operation is done on a global database across multiple regions.
How would the data propagation in this case for the global streams work? How would the atomicity be maintained in this case?