Antonyms for the phrase "street talks" could include formal conference, official meeting, structured dialogue, or professional discourse. These words imply a more organized and structured environment for discussion, as opposed to the informal and casual nature of street talks. Other possibilities include symposium, summit, seminar, or webinar, as these terms all suggest a setting where participants come together with a common purpose, rather than simply engaging in conversation on the street. Using antonyms for "street talks" can help convey a sense of formality and professionalism, while also emphasizing the importance and significance of the discussion topic.