Comment # 1 on bug 911152 from Johannes Meixner

For all-in-one devices the printer unit and the scanner unit
must be set up separated (a print queue for the printer unit
and a scanner driver for the scanner unit).

Only some scanners are set up automatically
(via the sane-backends-autoconfig RPM package)
but most scanners are not set up automatically.
Usually you must manually set up a scanner.
For general information see
https://en.opensuse.org/SDB:Configuring_Scanners

There is no generic way how to autodetect when there is
an optional PostScript unit in a printer device.
Therefore you must manually set it up as PostScript printer.
See also "Driver" at
https://en.opensuse.org/YaST_Printer
and "Printer drivers: Make the printer print" at
https://en.opensuse.org/Concepts_printing

HP's optional tools are not installed by default.
Therefore you must manually install HP's optional tools
(i.e. you must manually install the hplip RPM package).

Regarding multiple printer setup tools:
Usually there is no real conflict when multiple printer setup tools
are installed at the same time.
See also "Automated Printer Configuration" at
https://en.opensuse.org/YaST_Printer

In general regarding how to set up HP all-in-one devices see
https://en.opensuse.org/SDB:How_to_set-up_a_HP_printer

In general regarding bug reports versus asking support questions see
https://en.opensuse.org/openSUSE:Submitting_bug_reports

We (i.e. openSUSE) distribute HP's HPLIP software for HP printers
and HP all-in-one devices but we do not develop it. In case of
issues with HPLIP, you should report them directly to HP via
http://hplipopensource.com/hplip-web/support.html
so that there is a direct communication between you
and the upstream authors. 

I close this bug report as "invalid" because the described issues
are no real bugs (at least no bugs for openSUSE).