yep another one
no prep , in character , standard equipment , Round 1 - animated versions of both , Round 2 - comic versions of both
For those curious what Clow Cards Li had in the anime, here's the rundown: Dash, Dream, Freeze, Return, Sand, Storm, Time, Twin.
For the animated versions, I believe Robin would be screwed as the Clow Cards in Li's possession would give him some cheap means to dispatch the Boy Wonder such as use of Time or Freeze.
Manga version of Li isn't much different from the anime, though he's lacking the Clow Cards. I'd picture the comics version of Robin being able to win against manga Li after a prolonged fight. Robin is a more experienced fighter with skill in various styles of martial arts, though I could picture Li's use of his magic causing problems for Robin.