Link a Textract async operation with downstream process

I have a simple setup with one Lambda function that starts a Textract analysis of a document via StepFunctions.
The textract task in the StepFunction definition sends a notification on an SQS which triggers another lambda. I have little to no control on what message is sent in the SQS by textract since it's a predefined aws task.

Everything is patched with Xray and what it's seen from console is essentially this:
(client) -> LambdaA -> StepFunction -> Textract
(client) -> LambdaB (this one has been triggered by the SQS message)

However I was wondering if it is possible at all to link the two flows in Xray and see them as one trace_id or linked traces.

Can two traces be linked manually with the SDK?

まず AWS X-Ray SDK for Python の tracing API と、issue で説明されている Step Functions、Textract、SQS、Lambda の統合ポイントを確認します。SDK がこれらのフローを 1 つのトレースまたはリンクされたトレースに手動で関連付けることをサポートしているかどうかを判断し、サポートされる結果または制限事項を文書化します。

索引モデルが issue の本文から書いたものです。