Hi, @Laurent
Thank you for posting in Microsoft Q&A forum.
Here is a discussion about uploading hash during MDT, you may check if it helps:
https://www.reddit.com/r/Intune/comments/etxyz3/autopilot_auto_upload_hash_during_mdt/
And here is a detailed guidance to import hash during SCCM task sequence, you may check if it can be used in MDT:
https://credibledev.com/intune-hardware-hash-import-during-task-sequence/
We may also check: How to deploy Autopilot device fast with MDT:
https://osddeployment.dk/2018/12/08/how-to-deploy-autopilot-device-fast-with-mdt/
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