"Wert the up and up" is an informal way of saying that something is honest, legitimate, and acceptable. Antonyms for this phrase could include words such as "dishonest," "corrupt," "deceitful," "illegal," and "untrustworthy." These words describe actions and situations that are not above board and cannot be trusted. Other antonyms could include "false," "fraudulent," "illegitimate," "insincere," and "illusory." When something is not "wert the up and up," it suggests that there is something questionable or suspicious about it. It's important to be aware of these antonyms and to avoid situations that could be potentially harmful or unethical.