In the original French version, Cat Noir is known as "Chat Noir", which is French for "black cat". Most dubs translate his name totally or partially ("Cat Noir" in the English version; "Black Cat" in the Korean version). Cat Noir's name is also often changed in dubs, see the Gratuitous Foreign Language entry.
The Mandarin Chinese dub does translations and transliterations with character names. With Ladybug and Cat Noir, they mix both which causes some Repetitive Naming, as Ladybug's dub name translates back to "Ladybug Lady" in English, and Cat Noir's translates to "Cat Noir Noir" in French. Hawk Moth's dub name (加百利, jiābǎilì) doesn't reference a butterfly or any other dub name, but is instead a loose transliteration of "Gabriel" (加百列, jiābǎiliè).
Heroes
In the Latin American dub, Rose's name is Rosita.
In the Russian dub, Luka's name is changed to "Luke".
In the Serbian dub, Alix's name is changed to "Aleks"
In the Serbian dub, Mylène's name is changed to "Milena".
In various Romance languages, Kagami's name is too similar to the verb for "to shit" (cagar/cagare), so it was changed to Agami in Spanish, and Katami in Italian. In Brazil, where the same issue exists, they changed her name to Kyoko. As it happens, "kyo" (like "kagami") is another possible reading of the kanji for "mirror" (鏡), so "Kyoko" can be interpreted as "mirror-girl", maintaining her intended Meaningful Name.
Civilians
Chris is originally named as "Noel" in the French version. This keeps the Christmas/Noël pun of his introductory Akumatization.note (Noël becomes "Maître Noël", translating to 'Master Christmas,' so Chris becomes "Christmaster.")
In some dubs, Clara Nightingale first name changes from Clara to Laura, furthering the resemblance between her and her VA in the English dub.
Simon's name was changed from Jacques in the French Dub to Simon in the English dub, in order to preserve the Simon Says/Jacques a Dit pun.
Antagonists
In the Slovenian dub, Chloe Bourgeois is renamed to Clara Bourgeois.
Likely to avoid Fluffy the Terrible, Hawk Moth's name was changed from "Le Papillon", due to the name literally translating to "the butterfly". His French name is Le Papillon ("Butterfly")note Likely because "Hawk Moth" is literally impossible to pronounce in French, as its "h" sounds are silent and it has no "th" and in the Italian dub he's simply called Papillon, but he's known as Hawk Moth in the English and Korean dubs. His Hungarian name is Halálfej ("Death's-head"), while the European Spanish one is Lepidóptero ("Lepidopteran"). In Polish version he's called "Władca Ciem" ("Lord of the Moths")
Lila's name is pronounced "lie-lah" instead of "lee-lah" in the English, Chinese, Korean, and Russian dubs.
Lila known as Layla Rossi in the Brazilian dub, since that's the most common variation of the name over there.
Depending on the dub, her name is pronounced as either "lie-lah"note English, Korean, Russian, Mandarin Chinese or "lee-lah"note French, Italian, Spanish. The latter would be more fitting to her dubios Italian background and the French setting.
Sentimonsters
Reflekdoll is originally named as Poupeflekta the original French version.
Light Eye's is originally named as Pharo in the French dub.
