Abby Trott is well known for being the voice of Nezuko from Demon Slayer. She has been voice acting since 2013, so here are some characters that she voiced before Nezuko.
All of these are before October 12 2019 which was the day the first episode of the Demon Slayer English Dub released. For example while Abby did voice Riko Aida in Kuroko's Basketball which technically came out in 2012, the English Dub officially came out in 2021 meanwhile Demon Slayer's Dub came out in 2019 so that will not be considered for this list.
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Anilist Sync