While Sumipe has never, strictly speaking, voiced Nekomusume before (in an anime or game), she plays her TWICE in both stage adaptations.

GeGeGe no Kitaro 2025 Stage Play promo poster

(Yep, that's Solid Snake as Nezumi Otoko up there. Kitarou is played by some random ikemen a career actor though.)

Here's also an official clip from the older play 3 years ago (when Nekomusume's hair was still brown, and Nezumi Otoko had a different actor).