It’s best to wait.
If you were to look up all that information about them beforehand, you would have a preconceived notion of the person you are about to meet.
This could affect how you behave on the date due to a new set of expectations.
Besides, wouldn’t it be a lot more fun to get to know the person based off of your personal experience with them than off of a bunch of images, text and memes you see in relation to them online?
Nothing wrong with learning a little something about them but don’t go overboard. Save most of that curiosity for the real life meeting.