Disabling the Zone Awareness feature may lead to less resilient ElasticSearch clusters.
Zone awareness applies only to multi-az configurations.
In AWS Console -
In Terraform -
References:
https://docs.aws.amazon.com/opensearch-service/latest/developerguide/managedomains-multiaz.html
https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/elasticsearch_domain#zone_awareness_enabled