Players will now chatter during the games. What players say is related to their hidden personality characteristics. This gives more hints about player personalities. Some things to look for in general:
High Greed - tend to brag about themselves
Low Greed - tend to be selfless
High Loyalty - tend to praise the team
Low Loyalty - talk about leaving or complain about team in general
High Dedication - Make comments about working hard
Low Dedication - tend to talk about being lazy and not wanting to work
High Reliability - tend to use boring tropes and broad comments
Low Reliability - say and do crazy things or talk about vices
High Acceptance - tend to compliment opponents
Low Acceptance - tend to trash talk opponents
High Morale - talk about excitement or uplifting things
Low Morale - make defeated comments or complain about team performance
High Leadership - try to inspire specific teammates or pump up team
Low Leadership - tend to insult or threaten teammates
Combinations of these are used and what players say about others is also influenced by personality and performance.
In the settings menu you can turn off trash talk and filter out profane trash talk.