A clever speaker can speak on any
subject, either for or against.

[ἐκ παντὸς ἄν τις πράγµατος δισσῶν λόγων
ἀγῶνα θεῖτ᾽ἄν, εἰ λέγειν εἴη σοφός.]

Euripides (485?-406? BC) Greek tragic dramatist

Antiope [Αντιοπη], frag. 189 (TGF, Kannicht) [Chorus] (c. 410 BC)
    (Source)

Barnes frag. 79, Musgrave 39. (Source (Greek)). Alternate translations:

The skillful orator can either side
Maintain on every topic of debate.
[tr. Wodhall (1809)]

A man could make an argument for two sides of any
matter, if he were a clever speaker.
[tr. Will (2015)]