Romance Languages:
* Spanish: exitoso/exitosa (masculine/feminine)
* French: réussi/réussie (masculine/feminine)
* Italian: di successo
* Portuguese: bem-sucedido/bem-sucedida (masculine/feminine)
* Romanian: de succes
Germanic Languages:
* German: erfolgreich
* Dutch: succesvol
* Swedish: framgångsrik
* Danish: succesrig
* Norwegian: suksessfull
Slavic Languages:
* Russian: успешный (uspeshnyy)
* Polish: udany
* Czech: úspěšný
* Ukrainian: успішний (uspischnyy)
Other Languages:
* Chinese (Mandarin): 成功 (chénggōng)
* Japanese: 成功 (seikō)
* Korean: 성공 (seonggong)
* Arabic: ناجح (nājiḥ)
* Hindi: सफल (safal)
* Greek: επιτυχής (epitychís)
This is not an exhaustive list, but it gives you a good starting point. Remember that the specific nuances of the word "successful" can vary slightly between languages.