Tell MySQL to start using utf-8 encoding without `convert to`ing it
The solution isn't precisely the same but this question is where I originally found direction for a similar issue and the concepts there should take you where you want to go. MySQL has a BINARY character set and from all appearances, by converting through it, you can prevent MySQL from realizing what you're actually doing and being "too helpful."

Test case with character_set_client = utf8:

mysql&gt; select CONVERT(CONVERT(CONVERT('Mikeâ€™s' USING latin1) USING binary) USING utf8);
+--------------------------------------------------------------------------------+
| CONVERT(CONVERT(CONVERT('Mikeâ€™s' USING latin1) USING binary) USING utf8)     |
+--------------------------------------------------------------------------------+
| Mike’s                                                                         |
+--------------------------------------------------------------------------------+
1 row in set (0.00 sec)


You could use that logic to populate a new column that MySQL believes to be utf8.