Amazon Neptune announces support for versions 2.3 and 2.5 of Amazon OpenSearch for a Neptune versions and support for OpenSearch Serverless with Neptune engine version 1.2.2.0 and higher. This is in addition to previously supported Elasticsearch 7.1 or higher versions, to allow customers to perform full text search within their graphs. Customers can now use search indexing capabilities with OpenSearch 2.3 and 2.5 , and Serverless with their graph data stored in Neptune.
Source:: Amazon AWS