Waluigi has no game so if out of nowhere someone makes a game for him he could potentially go to smash otherwise he's going to be an assist trophy with that tennis racket. Waluigi was more of a rushed concept and has very few roles in major games and most of the time he's just a side character.
It's very rare if we could have him for DLC otherwise he would be the first ever to come as one of the main characters and an assist trophy. So they would save him for another smash or just leave his glory in Mario Tennis
