Lucario has no thumbs, so in the end, there'd be no grapple face-off. Plus, that guy has one arm. And are you comparing Lucario.VS.Wario with TwoArms.VS.OneArm? Even if they're both experts, one arm is a SEVERE disadvantage in a martial arts contest, you only have one weapon in terms of grappling: your one arm. Lucario has 2, and cannot grapple. This pretty much breaks it up.Sure, but that is only if Wario mindlessly rushes against Lucario and does exactly what he wants him to do, like in a practice. If we go by a real fight then it would end up with both opponents on the ground, grappling each other.
http://www.youtube.com/watch?v=R797LamA3Vw&feature=related
If Wario grabs Lucario by one arm and lifts him up, Lucario can jam a spike in Wario's face. No matter how pointy it is or isn't, a spike to the eye = bad time for you. He could also kick Wario's face, or continuously jab the spike in Wario's wrist (where the tendons are) and force Wario to let him go. After all, he's a martial artist, and a single-arm grab can be broken easily by any martial art.
Some "grapples" Lucario can do without a thumb, just by using his opponent's force against him, if Wario grabs Lucario (remember that Lucario has honed his reactions, he IS a martial arts expert, so it takes no more than simple movement for him to know what you're doing):
Wrist Grab
Kosa-Dori Koshinage = Using Wario's weight against him thanks to Lucario's leg strength.
Ikkyo Wrist Grab Defense
And what technique would Wario be doing against Lucario's Aikido, which he would just be using to guide Wario's forceful attempts to where he wants Wario to be? Does he have a written-down style of fighting, or is it just a "jump in, get your hands dirty" situation?
The OP gave him martial arts. We can assume Lucario, in a real-life scenario, has martial arts.BTW, where did it said that Lucario knows all fighting styles in the world? Looked at both bulbapedia and serebii, and found nothing.....