@Sokoban,Thanks for posting in Q&A.
From your description, I know you want to know what kind of permission do you need to copy a file to system32 folder.
Based on my research, to copy files to the System32 folder using a batch file, you need the administrative permissions and if prompted by User Account Control, click Yes to grant the batch file administrative permissions on targeted device.
Moreover, if you deploy the script via Intune, you should set Run this script using the logged on credentials No to run the script in system context.
Hope it will help.
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