I was thinking of "Eloquent", "Fluent" or "Persuasive" but feels like it's not what I want because the word I'm looking for isn't about how many words you know, you can be eloquent but your choice of words isn't that good.
I'm looking for a word to describe someone who is eloquent and smart at the same time. Like an expert lawyer talking to a judge.
"Persuasive" is the closest word to what I want but you can't tell your team of sellers "try to be persuasive with the customers". It's like selling them fake products.
I want my team of sellers to be _____.
Something like Christoph Waltz in "DJANGO UNCHAINED" and Leonardo dicaprio in "The wolf of wall street"