I own them both, and love them both, but The Wonderful 101 gets my nod as the better game.
The gameplay concept is very simple but it has a much steeper learning curve to mastery, and will absolutely brutalize rookies for any mistakes or shortcomings in combat, especially in the latter half of the game. The game does have its weaker moments(clunky indoor sequences, and a couple vague platforming way-findings directions), but they are easily overlooked once they're completed and you are thrown back into awesomeness again.
Once this game clicks though, it reveals itself as the absolute best in its genre. The combat is like nothing else before it, and the potential for original combos is quite amazing. Watching truly skilled players chain an onslaught of attacks together in their own unique ways is a sight to behold. You are in much more control of your play-style and how you combine attacks, as apposed to watching Bayonetta perform (beautiful) animations by a predetermined string of buttons presses. This aspect have had an immense impact on how gratifying combat feels in each game, and it's something that Bayonetta 2 - while still awesome - just can't measure up to. When you conbine the more interesting story, Saturday-morning-cartoon vibe, several charming main characters, way more interesting/clever boss battles, and the absolute best ending sequence of any action game... TW101 won me over - more so than Bayonetta 2 - quite easily!
I'd probably double dip on both if Platinum can lock them in at 1080p-60fps. Would even settle for 900p if performance is a concern.