rsync does not have the ability to copy a file using the filesystem's copy-on-write feature. This is unlike cp, which has the --reflink flag. Here's the bug report on GitHub which the developers closed as "won't fix for now":
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<a href="https://github.com/RsyncProject/rsync/issues/119#issuecomment-3769076742" rel="nofollow">https://github.com/RsyncProject/rsync/issues/119#issuecommen...
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