To be completely honest, sure. Leafeon has an decent Physical movepool in-game. These consist of Leaf Blade, X-Scissor, Iron Tail and Facade. Luckily, Leafeon gets Swords Dance and Synthesis via level up which makes it a potent sweeper. If you over level Leafeon some, you can easily get off a Swords Dance and plow through most teams. Also, most of the TM's are available mid game, so that should not pose a problem. So, while Leafeon certainly isn't the best Choice, I believe that it's access to Swords Dance and Strong STAB makes it a decent option. One thing, Leafeon learns Leaf Blade at level 45, so it is rather late. Also, anything can work fine in-game, as long as you level it up enough. Hope this helps!