In an Item Fulfillment, if the Shipping tab > Integrated Shipping Label = T, then you click Print Label, will it generate a label from Integration such as UPS/FedEx and not the default Advanced PDF/HTML Template?

It's not an Advanced PDF/HTML template. It'll download a ZPL file and you have to make a batch file to open and send it the label printer.

But if Integrated Shipping Label = T, Label should be generated by third party and will have the third party's look and format, right?