Well according to the rules:
https://octowow.st/rules#behavioral-expectations-tab-1
Chat Expectations
In order to maintain a healthy community and ensure our content remains accessible world-wide, we have some limitations on usages of our in-game chat service. We both look to safeguard younger players on our network, and allow players of all ages to escape from the stress of the real world and immerse themselves in Azeroth, with the following behaviors not allowed on our network:
Discussion of overtly sexual or otherwise vulgar topics.
Discussion of politics, religion, or other controversial matters or figures. Keep the politics exclusively Azerothian!
Encouragement of racism, sexism, homophobia, extremism, violence, doxxing, or other hate speech towards individuals/groups of people.
Insulting or otherwise harassing a player or group (such as a guild).
Attempting to impersonate another player, or a member of the OctoWow Team.
Use of non-default colors for your chat messages.
Promotion of phishing websites, cheats, or links containing explicit content.
Use of other characters to evade someone’s use of /ignore to end communication.
Use of any non-English language in public channels, with the exception of guild advertisements.
Repeatedly sending unreasonable mail to clog a player’s mailbox.
In specific "Insulting or otherwise harassing a player or group (such as a guild)." does not state that “slurs” are generally prohibited—it clearly depends on intent. It needs to be an insult or harassment to a player or group targeted by it. Otherwise, you’d get banned if someone calls your teammate an “asshole” and you then defended him by saying, “No, you’re wrong—he’s not an asshole; he’s actually the nicest guy ever” - Which would be absolutely crazy.