I'm pretty sure you can read it without prior knowledge of DC Comics. As long as you are familiar with the characters, that's enough.

You definitely don't need to read "all of DC Comics" to understand that or any other event.

They were meant as novelties, so just knowing the characters’ names is enough.

Perfect.

Crossovers like that know the readers will either only know one or the other. So don't expect much depth. Important characters will be explained in the series, minor characters are unimportant. DC events have no bearing onthe events of the crossover.

If you get any interests in reading DC comics after the crossover you can ask us, of course. DCs comic universe is vast and has a lot of stories you would love. Only reading from one company means you are going to miss out a lot of cool things!

However, diving into both companies (and others like Image, Dark Horse, Dynamite, Boom...) is a huge investment in terms of money, time and floorspace so don't ever feel compelled to.

If you haven't already, you should also check out DC Versus Marvel