Chiyuki Miura is a Japanse voice actress that is affiliated with the talent agency Ken Production
On November 28th, 2021, the official Japanese Twitter account posted an interview
and The Pokémon Company also posted a corresponding press release to promote PM2019 91 and PM2019 92.
"I was extremely happy when I learned I got cast. I've watched the Pocket Monsters TV series ever since I was a kid, and I have more memories tied to it than almost any other anime, so I can't believe I've going to be in it as THE Onion-kun! I gave the role my all, knowing that this is an extremely appealing character that lots of people really fell in love with when they played the video game, so he has to be portrayed with extreme care.
Onion-kun is so reticent it seems he's straight up bad at talking to people, which is precisely why I played every single word of his with great care while talking them over with the sound director. I'm looking forward to being able to bring you a new side of Onion-kun you didn't get to see in the video game, and I hope it will make you love him so much more. Please keep an eye on him as he tries his best in his own little way.
-Chiyuki Miura, voice of Onion