I tried test https://fedoraproject.org/wiki/QA:Testcase_Mediakit_Repoclosure
for Fedora-Server-dvd-ppc64le-28_Beta-1.3.iso

for powerpc, I used old method with repoclosure command

mount -o loop Fedora-Server-dvd-ppc64le-28_Beta-1.3.iso /media
dnf install yum-utils
repoclosure -a ppc64le --repofrompath myrepo,/media/ --newest -t -r myrepo

...
package: phpMyAdmin-4.7.8-1.fc28.noarch from myrepo
  unresolved deps: 
     (php-composer(google/recaptcha) >= 1.1 with php-composer(google/recaptcha) < 2)
     (php-composer(phpmyadmin/motranslator) >= 4.0 with php-composer(phpmyadmin/motranslator) < 5)
     (php-composer(phpmyadmin/shapefile) >= 2.0 with php-composer(phpmyadmin/shapefile) < 3)
     (php-composer(phpmyadmin/sql-parser) >= 4.2.3 with php-composer(phpmyadmin/sql-parser) < 5)
     (php-composer(phpseclib/phpseclib) >= 2.0.9 with php-composer(phpseclib/phpseclib) < 3)
     (php-composer(tecnickcom/tcpdf) >= 6.2 with php-composer(tecnickcom/tcpdf) < 7)

expected result:
none "unresolved deps" should be reported.

This problem is present on ppc64 and ppc64le