"Fiddles with" is a phrasal verb that can be replaced with multiple antonyms depending on the context. It can mean to "manipulate" or "tamper" with something, in which case antonyms would include "leave alone," "abstain from," or "avoid." Alternatively, "fiddles with" can mean to "play with" or "tinker" with something, in which case antonyms would be more positive, such as "nurture," "care for," or "improve." Another antonym for "fiddles with" could be "use decisively" or "take action," depending on the situation. It is essential to consider the context carefully when searching for antonyms for any word or phrase to avoid confusion.