If Pokémon Talked (Generation I) Role Re-Casting
KittyLuv090 for Clefairy/Clefable (Female)
Clefairy and Clefable are Fairy-Type Pokémon (formerly Normal-types). They are shy and timid Pokémon. They do not like fighting and prefer to live in quiet areas, so I would expect to have a high and sort of quiet voice. But also playful sounding at the same time. Clefairy would sometimes speak in 3rd person, and Clefable no longer have the 3rd person way of speaking, and would speak in a more mature sounding voice than Clefairy.
Clefairy: What a perfect night to start singing and dancing! Clefairy loves it so much!
Clefable: I was lucky enough to find a moon stone back when I was a Clefairy.
If you could make the Clefable voice higher, that would work better. I mean I actually imagined the voice for Clefable being identical, but not exactly like Clefairy.