I'm noticing that across our several databases and hundreds of tables that
column definitions are not consistent. I'm wondering if there is a tool or
query (using INFORMATION_SCHEMA perhaps) that will show me all databases,
tables and columns where they don't match (by column name).

For example in one table `foo_id` might be UNSIGNED and in other's it is
not. Or maybe it's INT(11) in some and INT(10) or worse MEDIUMINT in others.
Or extending further Charset/Collation might mismatch and be that stupid
"latin1_swedish_ci" and fixed to be "utf8" in others.

Stuff like that. I want to see everything where there is some difference.