Update unitprice in order view via a custom module
Vendor/Module/view/frontend/layout/sales_order_item_price.xml Vendor_Module::item/price/unit.phtml Vendor/Module/view/frontend/templates/item/price/unit.phtml

Vendor/Module/view/frontend/layout/sales_order_item_price.xml
Vendor_Module::item/price/unit.phtml
Vendor/Module/view/frontend/templates/item/price/unit.phtml
= "TEST" ?>