Hi, @Brandon Ho
Thank you for posting in Microsoft Q&A forum.
You may set the Product Key per Task Sequence in customsettings.ini, the customsettings.ini could be like:
[Settings] Priority=TaskSequenceID, Default
[Default]
xxx=xxx
xxx=xxx
xxx=xxx
[W2016]
ProductKey=XXXX-YYYY-ZZZZ-AAAA
[W2019]
ProductKey=EEEE-BBBB-CCCC-DDDD
For your reference:
https://www.deployvista.com/2010/05/24/settings-per-task-sequence-using-mdt-2010/
(Please Note: Since the website is not hosted by Microsoft, just for your reference.)
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