It is a known issue and blizzard refuses to fix it.
https://us.forums.blizzard.com/en/wow/t/cant-transmog-weapons-after-switching-covenants/795866/62
It is a known issue and blizzard refuses to fix it.
https://us.forums.blizzard.com/en/wow/t/cant-transmog-weapons-after-switching-covenants/795866/62