Amazon EC2 Placement Groups are now available on AWS Outposts

AWS Outposts is a fully managed service that extends AWS infrastructure, AWS services, APIs, and tools to virtually any datacenter, co-location space, or on-premises facility for a truly consistent hybrid experience. Amazon Elastic Compute Cloud (Amazon EC2) placement groups allow you to influence the placement strategy of instances on the underlying hardware. You can select from cluster, spread or partition placement strategies, depending on the needs of the workload.

Source:: Amazon AWS