Kotlin TextractAsyncClient Not Implemented?

I apologize, but there seems to be a misunderstanding in your question. The AWS SDK for Kotlin is indeed available and supports many AWS services, including Amazon Textract. However, the specific implementation details you're asking about aren't explicitly mentioned in the provided sources.

The AWS SDK for Kotlin was announced as generally available in November 2023. It's designed to provide an idiomatic Kotlin experience, including support for coroutines for asynchronous AWS service calls. This SDK supports access to over 300 AWS services, which should include Amazon Textract.

While the exact class TextractAsyncClient isn't specifically mentioned in the sources, the SDK for Kotlin does offer asynchronous capabilities through coroutines. Instead of looking for a TextractAsyncClient, you might want to look for a TextractClient that supports coroutine-based asynchronous operations.

If you're having trouble finding the appropriate client or methods, you may want to check the AWS SDK for Kotlin documentation or GitHub repository for the most up-to-date information on how to use Amazon Textract with Kotlin. The SDK is relatively new, so it's possible that some implementations or documentation might still be in progress.

If you absolutely need to use TextractAsyncClient and can't find a Kotlin equivalent, using the Java SDK within your Kotlin project is a viable alternative, as Kotlin is fully interoperable with Java. However, for the best Kotlin experience, I'd recommend exploring the Kotlin SDK further or reaching out to AWS support for the most current information on Textract support in the Kotlin SDK.
Sources
AWS SDK for Kotlin is now generally available
Announcing general availability of the AWS SDK for Kotlin | AWS Developer Tools Blog