Animate my 3d character for existing Unity game

hi i have this game : [login to view URL]!/content/32543 , so was planning to replace the characters in the game by 5 other characters like these : [login to view URL]!/content/8420 so need the character animation existing like in the game to be added to these 5 characters . the animation of character in game was not possible to be added to the smoo characters coz it wasn't humanoid so needed a similar animation to be added to these smoo characters.