Yes, corn snakes do tend to be more active during the day when compared to a ball python, since they will move back and forth more frequently between hides, but even they seem to be the most active in the evening. There isn't anything wrong with taking your ball python out during the day either though, usually they'll just go back and hide after you put them back.

And no, I wouldn't recommend housing two of them together. I know there are some people who do it, but I personally think it's more stressful for the snakes.