Ballin' is urban American slang for "playing basketball".
The song steps in and out of using it literally and metaphorically.
Literally, "ballin' you" means "beating you at basketball". And you can understand the song in a literal sense to praise the game of basketball and the star players they mention.
Metaphorically, "ballin' you" can be applied to any type of competition. You can understand the song as a metaphor for any activity in your life where you are talented, doing all the right things, and better than others.
Another way to understand "ballin' you" is from the viewpoint of the artists. Michael Jackson and Ice Cube didn't play professional basketball but they were beating their competition in Pop music and Rap music at the time. And they teamed up to make this song in the same way they sing about being on the same team as basketball stars.