In this case your issue is related to the product label report. Check the corresponding report and the related QWeb view and then ask a corresponding question about the "code" widget used in the report.product_simple_label QWeb view. This might give you the idea: https://www.odoo.com/forum/help-1/question/how-to-display-the-barcode-in-sales-order-window-odoo-10-117968

Sorry your suggestion is not clear, I need just to print the label from

Inventory --> Product --> SpecificProduct --> Print --> Print product label.

this is working for numeric barcode, but it is not working for alphanumeric barcode

You have to customize the label report accordingly. The problem is the code widget which obviously only accepts numerical barcodes.

You could also check this module on how to create a new bar code type: https://www.odoo.com/apps/modules/10.0/barcode_widget/