@San TCI, Thanks for posting in Q&A. In Intune portal, we can bulk rename device directly, this feature uses the same rules as renaming a single device. You can try the name format like ABC-{{serialnumber}}
https://learn.microsoft.com/en-us/mem/intune/remote-actions/device-rename#bulk-rename-devices
If you want to rename device via script, here is a link list the script you can refer:
https://timmyit.com/2023/06/23/intune-rename-devices-with-powershell-and-microsoft-graph-module/
Note: None-Microsoft link, just for the reference.
Hope the above information can help.
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