Hi,

I tried the same Example using V15EE but unfortunately, integrated barcode scanner is not working neither do i have a physical barcode scanner..

In this case you will have to check code because i think even if you scan barcode, it's just not "catched by Odoo". To check this you can:
1- target function _step_product in: stock_barcode/static/src/js/client_action/abstract_client_action.js:1085
2- Before line 1136 having: if (! self.scannedLines.length) {
you print : console.log('Result', ! self.scannedLines.length)

3- If True, then as i said even if you scan barcode, odoo does not recognize scanned lines..
4- you can report the bug to Odoo directly via odoo.com/help
5- I'm starring your question as i'm also interested in knowing what's wrong.

I hope this helps you.
thanks

Hello,

In odoo EE v15 barcode application this error also render when you try to scan the package of child location. 

In header section of barcode application you can show the from and to locations. First adjust the from location according to package location and scan the package. I think package will scan successfully.

shivoham.odoo@gmail.com