Guidelines can be found here:
This paragraph specifically applies (bolding mine):
- Do not deliberately misgender another poster – that is, refer to them by a pronoun or other sex-specific term indicating a gender other than the one they identify as. This applies only in cases where a poster’s gender identity is reasonably clear. Likewise, do not deliberately misgender off-board figures. This is a more rigorous standard than we apply in other contexts; we do not normally mod posters for merely insulting off-board figures. Deal with it.