Greetings,

In patch 2.28 we are planning to make it so you can set the following to your hotbar using the “/hotbar set” command.
  • Companion actions
  • Pet actions
  • Minions
  • Mounts
  • General actions
  • Emotes
  • Items
  • Target markers
  • Waymarks

Please note, however, that this is still being planned and may be subject to change.