Hello,

The Unit of measurement is imported as a meta field of the product: https://monosnap.com/file/Rggfe4l1PTvaQxsROLJWRgoAzLyHWA

When you configure the import, you need to set Import as metadata.

We have tested that on your site and it works properly: https://monosnap.com/file/LXZurO2L3ngwQETOm2xp7aHtYnkXxP

If you have any questions please feel free to contact us.

Best Regards