Let me tell ya, drawing a fight between them and making it look suitably non-silly was not easy. They can still be pretty lithe beneath all that fluff (I imagine it’s so poofed out they look a lot fatter than they are), but close-quarters fighting still looks like two cotton balls mashed together.
Reflections can be deceiving, so if you count mirrors and water reflections as fluffelgangers then yes! From Wawa’s Visitors chapter 2:
As they looked for a way to cross the shallow stream safely, Smarty refusing to let his pregnant mate wade across the water, the tired Blueberry was talking to her reflection. It consoled her and listened to her sorrows until she leaned down to thank it. When she did, the waves raised and cradled her head before suddenly grabbing hold, dragging her face below the surface. The other fluffies panicked; both stallions grabbed hold of her tail and pulled as hard as they could, but by the time they tore her free from the water it was too late. Blueberry had been drowned.
And from Toy Castle chapter 8:
Snowcone approached the water and looked down at the clear surface, faced with her own reflection. (…) Below the surface swam thin fishes, and Snowcone eased somewhat as she murmured. “Hewwo, fishy fwiends.”
Mimicking the words, her reflection tilted its head with a thin smile, and Snowcone scrambled away from the water.