Due to age and injury problems, it is often possible to change the voice actor of the character in long-running anime. But when the sound you're used to suddenly changes, doesn't that surprise you? Recently, the Japanese website "goo ranking" voted for the character leaderboard that surprised you due to the change of voice actors in the middle.
Among them, Doraemon in "Doraemon", which has changed voice actors three times, ranked first. Doraemon's first three months were voiced by Koso Tomita, and the next three months were voiced by Masako Nozawa. From 1979 to 2005, it was voiced by Ōyama Kenshiro, most recently by Mizuta Wasabi. Although the early Doraemon were low male voices, it was later determined for the neutral voices heard now.

In second place is Maori Kogoro in Detective Conan. Ritsuya Koyama, who is currently the voice of Kogoro Maori, has appeared as a cameo voice actor several times before. On October 31, 2009, he officially replaced Akira Kamiya and began dubbing the main character of Maori Kogoro.
Lupin III in Lupin III tied for second place with the same vote. Lupin III has changed voice actors twice since the beginning, and was first voiced by Yasuo Yamada for Lupin III. Noboru Furukawa only dubbed a theatrical version in the middle, which was later voiced by Kurita Kanichi.
The following is the top 10 rankings,
1. Doraemon (Doraemon)
2. Maori Kogoro (Detective Conan)
2. Lupin III (Lupin III)
4. Hiroshi Nohara ("Crayon Shin-chan")
5. Kiki (Dragon Ball)
6. Cherry apricot (Cherry Pills)
6. Isano Bonito (Miss Conch)
8. Nobita (Doraemon)
9. Hapei Isono (Miss Conch)
9. Yukiichi Katakata (Lupin III)