COLLATION ‘utf8_general_ci’ is not valid for CHARACTER SET ‘latin1’

First, run this query:

SHOW VARIABLES LIKE '%char%';

You have character_set_server="latin1" shown in your post …

So, go into your my.cnf and add or uncomment these lines:

character-set-server = utf8
collation-server = utf8_unicode_ci

Restart the server.