Having been a journalist as a young man, Ernest Hemingway practiced writing in a clear, simple style that was economical. That is, he did not write sentences that had many introductory words or descriptive words, or transitional words. On the other hand, William Faulkner wrote sentences that were often at least half a page long. While eloquent, these sentences are very, very complex, containing many nonessential clauses, and descriptive phrases. However, in a story such as "Barn Burning" which has the simple agragian Snopses, writing a conversation in the fashion of their dialects could be easier, and probably funnier. The Snopses, use language that is very telling about their personalities. For instance, these thoughts of the ten-year-old protagonist, Sartoris, from "Barn Burning" indicate his feeling of vengeance that will wipe out everything, his wish to rid himself of all that troubles him, and his childishness in thinking all his problems will be solved "for ever."
Maybe it will all add up and balance and vanish—corn, rug, fire; the terror and grief, the being pulled two ways like between two teams of horses—gone, done with for ever and ever.
Thus, to write a conversation in the Faulknerian style, you may wish to simply imitate the diction of such a character as Sartoris Snopes, whose childish imaginings are in the superlative.
Two stories of Hemingway's that would assist the writing of a dinner conversation are "Hills Like White Elephants" and "A Clean Well-Lighted styles of Place," for these both have Hemingway's conversations that illustrate his signature "iceberg effect." That is, while the conversations seem rather mundane, there is much meaning beyond the surface. For instance, the man and the woman in "Hills Like White Elephants" talk in cryptic sentences with a tauntness of description; that is, they seem at first as though they speak of something inconsequential when in reality their subject is the very serious topic of abortion:
‘Then what will we do afterwards?’
‘We’ll be fine afterwards. Just like we were before.’
‘What makes you think so?’
‘That’s the only thing that bothers us. It’s the only thing that’s made us unhappy.’
So, in the dinner conversation, one character can be like a Hemingway character--terse with hidden meanings while the other can be Faulknerian--exaggerated and at the same time childish.