problem with installed package libexempi3-2.4.5-36.48.i586

zypper dup --download-in-advance
Retrieving repository 'Main Repository (NON-OSS)' metadata ...............[done]
Building repository 'Main Repository (NON-OSS)' cache ....................[done]
Retrieving repository 'Main Repository (OSS)' metadata ...................[done]
Building repository 'Main Repository (OSS)' cache ........................[done]
Loading repository data...
Reading installed packages...
Warning: You are about to do a distribution upgrade with all enabled repositories. Make sure these repositories are compatible before you continue. See 'man zypper' for more information about this command.
Computing distribution upgrade...
2 Problems:
Problem: problem with installed package libexempi3-2.4.5-36.48.i586
Problem: vlc-vdpau-3.0.12-312.1.i586 requires vlc-noX = 3.0.12, but this requirement cannot be provided

Problem: problem with installed package libexempi3-2.4.5-36.48.i586
 Solution 1: install libexempi3-2.4.5-1.13.i586 (with vendor change)
  obs://build.opensuse.org/multimedia  -->  openSUSE
 Solution 2: keep obsolete libexempi3-2.4.5-36.48.i586

Choose from above solutions by number or skip, retry or cancel [1/2/s/r/c/d/?] (c): 1

Problem: vlc-vdpau-3.0.12-312.1.i586 requires vlc-noX = 3.0.12, but this requirement cannot be provided
  not installable providers: vlc-noX-3.0.12-312.1.i586[http-download.opensuse.org-07cd078d]
 Solution 1: install vlc-noX-3.0.12-312.1.i586 (with vendor change)
  http://packman.links2linux.de  -->  obs://build.opensuse.org/multimedia
 Solution 2: install vlc-vdpau-3.0.11.1-8.1.i586 (with vendor change)
  obs://build.opensuse.org/multimedia  -->  http://packman.links2linux.de
 Solution 3: keep obsolete vlc-vdpau-3.0.11.1-310.1.i586
 Solution 4: break vlc-vdpau-3.0.12-312.1.i586 by ignoring some of its dependencies

Choose from above solutions by number or skip, retry or cancel [1/2/3/4/s/r/c/d/?] (c): 1
Resolving dependencies...
Computing distribution upgrade...
2 Problems:
Problem: vlc-qt-3.0.11.1-8.1.i586 requires vlc-noX = 3.0.11.1-8.1, but this requirement cannot be provided
Problem: vlc-noX-3.0.12-312.1.i586 requires libvlc5 = 3.0.12-312.1, but this requirement cannot be provided

Problem: vlc-qt-3.0.11.1-8.1.i586 requires vlc-noX = 3.0.11.1-8.1, but this requirement cannot be provided
  not installable providers: vlc-noX-3.0.11.1-8.1.i586[packman]
 Solution 1: install vlc-qt-3.0.12-312.1.i586 (with vendor change)
  http://packman.links2linux.de  -->  obs://build.opensuse.org/multimedia
 Solution 2: do not install vlc-noX-3.0.12-312.1.i586
 Solution 3: break vlc-qt-3.0.11.1-8.1.i586 by ignoring some of its dependencies

Choose from above solutions by number or skip, retry or cancel [1/2/3/s/r/c/d/?] (c): 1

Problem: vlc-noX-3.0.12-312.1.i586 requires libvlc5 = 3.0.12-312.1, but this requirement cannot be provided
  not installable providers: libvlc5-3.0.12-312.1.i586[http-download.opensuse.org-07cd078d]
 Solution 1: install libvlc5-3.0.12-312.1.i586 (with vendor change)
  http://packman.links2linux.de  -->  obs://build.opensuse.org/multimedia
 Solution 2: install vlc-vdpau-3.0.11.1-8.1.i586 (with vendor change)
  obs://build.opensuse.org/multimedia  -->  http://packman.links2linux.de
 Solution 3: keep obsolete vlc-vdpau-3.0.11.1-310.1.i586
 Solution 4: break vlc-noX-3.0.12-312.1.i586 by ignoring some of its dependencies

Choose from above solutions by number or skip, retry or cancel [1/2/3/4/s/r/c/d/?] (c): 1
Resolving dependencies...
Computing distribution upgrade...
4 Problems:
Problem: vlc-3.0.11.1-8.1.i586 requires vlc-noX = 3.0.11.1-8.1, but this requirement cannot be provided
Problem: vlc-qt-3.0.12-312.1.i586 requires vlc-noX = 3.0.12-312.1, but this requirement cannot be provided
Problem: vlc-noX-3.0.11.1-7.4.i586 requires libvlc5 = 3.0.11.1-7.4, but this requirement cannot be provided
Problem: vlc-codecs-3.0.11.1-8.1.i586 requires vlc-noX = 3.0.11.1, but this requirement cannot be provided

Problem: vlc-3.0.11.1-8.1.i586 requires vlc-noX = 3.0.11.1-8.1, but this requirement cannot be provided
  not installable providers: vlc-noX-3.0.11.1-8.1.i586[packman]
 Solution 1: install vlc-3.0.12-312.1.i586 (with vendor change)
  http://packman.links2linux.de  -->  obs://build.opensuse.org/multimedia
 Solution 2: do not install vlc-noX-3.0.12-312.1.i586
 Solution 3: break vlc-3.0.11.1-8.1.i586 by ignoring some of its dependencies

Choose from above solutions by number or skip, retry or cancel [1/2/3/s/r/c/d/?] (c): 1

Problem: vlc-qt-3.0.12-312.1.i586 requires vlc-noX = 3.0.12-312.1, but this requirement cannot be provided
  not installable providers: vlc-noX-3.0.12-312.1.i586[http-download.opensuse.org-07cd078d]
 Solution 1: install libvlccore9-3.0.12-312.1.i586 (with vendor change)
  http://packman.links2linux.de  -->  obs://build.opensuse.org/multimedia
 Solution 2: do not install vlc-qt-3.0.12-312.1.i586
 Solution 3: break vlc-qt-3.0.12-312.1.i586 by ignoring some of its dependencies

Choose from above solutions by number or skip, retry or cancel [1/2/3/s/r/c/d/?] (c): 1

Problem: vlc-noX-3.0.11.1-7.4.i586 requires libvlc5 = 3.0.11.1-7.4, but this requirement cannot be provided
  deleted providers: libvlc5-3.0.11.1-7.4.i586
 Solution 1: install vlc-codec-gstreamer-3.0.12-312.1.i586 (with vendor change)
  http://packman.links2linux.de  -->  obs://build.opensuse.org/multimedia
 Solution 2: do not install libvlc5-3.0.12-312.1.i586
 Solution 3: break vlc-noX-3.0.11.1-7.4.i586 by ignoring some of its dependencies

Choose from above solutions by number or skip, retry or cancel [1/2/3/s/r/c/d/?] (c): 1

Problem: vlc-codecs-3.0.11.1-8.1.i586 requires vlc-noX = 3.0.11.1, but this requirement cannot be provided
  deleted providers: vlc-noX-3.0.11.1-7.4.i586
not installable providers: vlc-noX-3.0.11.1-5.1.i586[download.opensuse.org-oss]
                   vlc-noX-3.0.11.1-5.1.i586[http-download.opensuse.org-8821fd0a]
                   vlc-noX-3.0.11.1-5.1.i586[http-download.opensuse.org-9ca73b56]
                   vlc-noX-3.0.11.1-5.1.i586[openSUSE-20200227-0]
                   vlc-noX-3.0.11.1-8.1.i586[packman]
 Solution 1: deinstallation of vlc-codecs-3.0.11.1-7.4.i586
 Solution 2: install vlc-vdpau-3.0.11.1-8.1.i586 (with vendor change)
  obs://build.opensuse.org/multimedia  -->  http://packman.links2linux.de
 Solution 3: keep obsolete vlc-vdpau-3.0.11.1-310.1.i586
 Solution 4: break vlc-codecs-3.0.11.1-8.1.i586 by ignoring some of its dependencies

Which repo is please best to use ?

Multimedia-libs Repo and Packman Repo together is not the best choice.

I use only Packman.

Thank you, I’ve switched to Packman and it has solved the issue.