Speak to them in private and let them know how you feel and let them know that you won't stand for it. Speak to their supervisors or Human Resources if that doesn't work.
British
Outspoken?
Someone who speaks dramatically and impressively could be called a declaim or an orator.
You could call someone who speaks two languages but not well a "basic or intermediate speaker" in both languages.
The common term for someone who speaks several languages is "multilingual."
unemotional
Someone who speaks directly or openly, without equivocation is someone who speaks with candor.
It could be a polyglot, someone who speaks several languages.Such a person could also be described as polylingual.
you call them a speaker that speaks in situations...?
talks poorly about someone.
A linguist is someone who studies languages. Apolyglot is someone who speaks more than 2 languages.
That would be a disciple.