Аж самому интересно стало...
А смотри что есть:
AWS_VPC_K8S_CNI_CUSTOM_NETWORK_CFG
Type: Boolean
Default: false
Specifies that your pods may use subnets and security groups that are independent of your worker node's VPC configuration. By default, pods share the same subnet and security groups as the worker node's primary interface. Setting this variable to true causes ipamd to use the security groups and VPC subnet in a worker node's ENIConfig for elastic network interface allocation. You must create an ENIConfig custom resource for each subnet that your pods will reside in, and then annotate or label each worker node to use a specific ENIConfig (multiple worker nodes can be annotated or labelled with the same ENIConfig). Worker nodes can only be annotated with a single ENIConfig at a time, and the subnet in the ENIConfig must belong to the same Availability Zone that the worker node resides in. For more information, see CNI Custom Networking in the Amazon EKS User Guide.
https://github.com/aws/amazon-vpc-cni-k8s