Honestly, I blame the game's shitty static animation/graphics.>hands are just constantly splayed off to the sides>tongue is just an oval constantly hanging out of its mouth>doesn't really look mischievous, just keeps a permanent thousand-yard-stare like the MCs in Sun/Moon
If it hopped around and chuckled and maybe occasionally stuck its tongue out and generally acted like a mischievous little shit, that alone would redeem the design quite a bit.
But yeah those oval feet and stick figure limbs are pretty fucking bad. I guess they were trying to make it cute and marketable even though it's an imp which defeats the point. I still have hopes for the evolution to look good.