We don't have synonyms for hellenise yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are hellenic, hellene and Hellenic.
(v) :
Non-Oxford British English standard spelling of Hellenize. [(intransitive) To use the language and culture of the ancient Greeks, to become Hellenistic.]
(v) :
Non-Oxford British English standard spelling of Hellenize. [(intransitive) To use the language and culture of the ancient Greeks, to become Hellenistic.]