I'l put all of the posted references from other threads here, so that they are all in one thread.
Warios sleeping animation in Brawl, looks a lot like the one from Lands 2 & 3:
First posted by: Bobo
The Shoulder Charge is in Mario Golf World Tour:
First posted by: Me/Warelander
Game & Watch Gallery 4 features Wario Land characters:
First posted by: CM30
The wild swing ding is one of Warios throws in Smash.
First posted by: Bobo.
The Wario Courth in Mario Tennis 64 has some Land 3 elements, like the theme song, keys, treasure chests and an odd resemplance to the Desert Ruins level:
Warios factory from Mario Power Tennis has Ware styled artworks and a remix of Wario Worlds hub world theme.
The warehouse courth from Mario Tennis Gbc has the Land 3 theme and Warios plane.
Wario Dunes from Mario Tennis Open has the Land 3 theme
First posted by: Me, thought CM30 mentioned parts of Warios Factory in this thread already.