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?

Beginne mit der Durchsicht der Tracing-APIs des AWS X-Ray SDK for Python sowie der in diesem Issue beschriebenen Integrationspunkte von Step Functions, Textract, SQS und Lambda. Ermittle, ob das SDK das manuelle Verknüpfen dieser Abläufe zu einem Trace oder zu verknüpften Traces unterstützt, und dokumentiere das unterstützte Ergebnis oder die Einschränkung.

Vom Indexierungsmodell aus dem Issue-Text verfasst.