Hi @Said A
Per my test, if we enable the feature of "require check out" in SharePoint, the files synced to OneDrive will all be locked:
The reason could be the following:
"When syncing libraries that require check out, or libraries with required columns or metadata, the files are synced as read-only. If you do make changes to these files, the changes will not be synced back to Office 365."
Here is a similar issue for you to refer to:
https://techcommunity.microsoft.com/t5/onedrive-for-business/read-only-padlock-icon-files-ofdb-17-3-6743-1212/m-p/38428#M952
You could send feedback to Microsoft SharePoint Feedback so that this problem could be resolved one day.
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