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Based on my research, Move to/ Copy to functions in SharePoint server have some limitations compares to SharePoint Online.
I found this discussion that might be helpful.
SharePoint (on-premises) Copy/Move To Another Library Or Site - Microsoft Q&A
How to move documents from subsite library to main site library SharePoint 2019 On prem - SharePoin…
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You cannot move a library from one to another site via the UI.
So please take a look at SharePointPnPPowerShell2019, using Copy-PnPFile.
You can install the module via PowerShell Gallery | SharePointPnPPowerShell2019 3.6.1902.2
Install-Module -Name SharePointPnPPowerShell2019 -RequiredVersion 3.6.1902.2
powershell/documentation/Copy-PnPFile.md at dev · pnp/powershell · GitHub
I hope this information helps.
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