Unfortunately, when you try to import the only Inventoria Fields you probably would see are:
Itemcode, Description, Category, Location, Quantity, Cost Price, Sales Price, Tax. But there is no option for Unit of Measure to a field in Inventoria
The only options available are the ones you see there when importing. There is no way to add more or change them. You will need to add that extra information in the description after you import the items.
You can confirm with NCH Technical Support if you like: https://www.nch.com.au/support/index.html