Homographs are words that are spelled the same but have different meanings and sometimes different pronunciations.
Among the pairs you provided, the pair "bat, bat" could be considered homographs as it can refer to a flying mammal or a piece of sports equipment, and both meanings are pronounced the same.
The other word pairs—"map, tap," "their, there," and "yes, no"—are not homographs, as they either have different spellings or are not the same word.
So the answer is: bat, bat.