Hi,
I would like to know if it is possible to install packages in AUR, or from Source (like .tag.gz), using YAST2 in order to keep track and to manage the history and packages dependencies using the very useful tools in YAST2.
Thanks 
you can always use alien to convert deb and tgz (slackware) to rpm and install them with zypper rpm or yast
https://software.opensuse.org/package/alien
afaik Arch is a lot younger then alien and it has no arch support but you could always convert the tar.xz arch pkg to slackware tar.gz and then let alien convert it to rpm
about building from source take a look at the rpmbuild script
man rpmbuild or read up on rpm spec files
https://en.opensuse.org/openSUSE:Specfile_guidelines
you’d need to write a spec file for the rpm you’d like to build from source it’s not that dificult even for non programmers but the thing is there is a high probobillith that the package you’re building has already been build on OBS so first try searching for it
https://software.opensuse.org/find
I did some reading and apparently alien does support xz compression in deb files and lzma in rpm but I couldn’t find any info about tar.xz or newer slackware tlz tbz or txz (which is the same as arch’s pkg)
you could ask the developers to add tar.xz pkg support as that seams doable and then all Linux distro’s would have a way to convert packages
https://sourceforge.net/p/alien-pkg-convert/discussion/
actually I’m surprised the Arch developers haven’t done this on their own as they do have an alien package for arch
https://aur.archlinux.org/packages/alien_package_converter/
Thanks very much.
I will test these options with a few packages