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See The Cornell “Standard” AWS VPC.
Can I coordinate Availability Zones with other AWS accounts?
While it may seem like a useful configuration to coordinate your "Availability Zone A" resources with another AWS account's "Availability Zone A", there is no way to guarantee you are both referencing the same Availability Zone in a given AWS Region. According to the AWS documentation on Regions and Availability Zones, there is a unique mapping of Availability Zone letter designations for each AWS account to ensure distribution of load across their infrastructure.