@Ariela Randall Thanks for posting in our Q&A.
For this issue, I have done some research. I find that the following links that list some methods may give us some inspiration. We can refer to them:
https://www.anoopcnair.com/intune-learn-to-deploy-windows-10-language-pack-step-by-step-mem/
https://oliverkieselbach.com/2020/04/22/how-to-completely-change-windows-10-language-with-intune/
Note: Non-Microsoft link, just for the reference.
Hope it will help.
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