This is a guide to copy data off an old NTFS disk to a TrueNAS ZSF pool attached to the same device. Using a Windows computer and SMB Shares to copy things to a pool is far safer.
TrueNAS (as of Dec 12, 2025) does not have a native way of mounting this drive. For my case, that was fine, as I only wanted to copy the data off an old Windows HDD onto into my big storage zpool, and I did not wish to go grab a Windows machine for just this one usage.
This is all to be done at your own risk. Computers can be spiteful, so make a backup, or do this only on a fresh system.
Done on TrueNAS SCale OS Version: 25.10.0