
Quick answer — Rika Nagae voices Olivia in Asobi Asobase - workshop of fun -, Hinata Hoshino in WATATEN!: an Angel Flew Down to Me, Mitsuha Yamano in Saving 80,000 Gold in Another World for My Retirement and 11 more characters.
Rika Nagae voices Olivia (Asobi Asobase - workshop of fun -), Hinata Hoshino (WATATEN!: an Angel Flew Down to Me), Mitsuha Yamano (Saving 80,000 Gold in Another World for My Retirement), Chiba (Wotakoi: Love is Hard for Otaku), Yaiba Shirogane (TONIKAWA: Over The Moon For You ~High School Days~), Yuna (Food for the Soul), Yuriko Kitahara (ONIMAI: I'm Now Your Sister!), Komachi Aizome (Go! Go! Loser Ranger!) and 6 more.
Olivia is voiced in Japanese by Rika Nagae.