I will edit my previous post to change the wording.
The documentation is apparently incorrect.
Using this source: Specifications> Paper Handling
Assuming the ability to print A4 borderless is there, I would guess that the issue might be one of the printer software not reading the settings correctly, the settings not being configured completely, or the installation of the software needs to be removed and reloaded.
If you did indeed completely remove all the printer software, including any leftover bits in Devices and Printers and the software that hides in the user account, then reinstalling again will not likely fix the problem.
That leaves that the configuration may not be set - since the A4 is not listed in the Specifications as supporting borderless, perhaps you had a custom shortcut created for this setting that included the A4 as a custom paper size for borderless printing. Ordinarily, custom shortcuts might survive reloading the software - not always and not when all traces of the previous installation of that software were removed prior to reinstalling the printer software.
If you have not done so, consider trying the HP Smart for Windows software.
General Example - HP Smart for Windows - Officejet Pro 9025 - Borderless print
The basic driver that is available is dated as having been released in 2017 - I am not aware of an older driver.
I will take my leave - I am not able to answer the question based on the information I can find.
I offer my apologies for wasting our time.
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