
Quick answer — Ikuko Tani voices Moominmamma in Moomin, Ito Nishimiya in A Silent Voice, Store Owner in Ghost in the Shell: Stand Alone Complex 2nd GIG and 17 more characters.
Ikuko Tani voices Moominmamma (Moomin), Ito Nishimiya (A Silent Voice), Store Owner (Ghost in the Shell: Stand Alone Complex 2nd GIG), Chizu Sakanaka (Natsume's Book of Friends Season 2), Shinou Harumiya (Erin), Huilian Jiang (Scissor Seven), Lizzie Bareare (Overlord), Miranda Holbrooke (Little Witch Academia (TV)) and 12 more.
Moominmamma is voiced in Japanese by Ikuko Tani.