@TCStevie, Thanks for posting in Q&A.
From your description, I know you are looking for a policy to change the Windows language via Intune.
Based on my research, we can download the language pack, convert it to .Intunewin file and upload it into Intune, then you can deploy it as win32 app. When you download the win32 app, the windows language will change.
Here are some links with detailed information you can refer.
For Windows 11: https://www.inthecloud247.com/how-to-change-the-windows-11-language-with-intune/
Non-official, just for reference.
For Windows 10: https://www.anoopcnair.com/deploy-windows-app-win32-using-intune-language/
Non-official, just for reference.
Hope it will help, if there is any update, feel free to contact me.
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