[AlanYx]

"wine dark sea" is the best example of this. It's a poetic/literary leap by Chapman and Pope that then became a functional convention in most subsequent translations.

The alternative translations aren't any better though, at least in English.

[dash2]

The original is οινοπα ποντον which indeed is very close to wine-dark sea. Literally "wine-faced" where -faced is a metaphor for "having the appearance of".

[AlanYx]

Literally "wine-faced" or "wine-eyed", yes. The problem with the literal wine-faced/wine-eyed is it doesn't convey luminosity/depth to readers, so it kind of misses the point. The missing context is that ancient wine was often unfiltered and cloudy, and diluted before being served.

"wine-looking" would be better for modern readers in terms of conveying the actual meaning, but again, it doesn't convey the actual idea Homer is getting at, and sounds awkward to repeat.

It's fun to think about alternatives far from the text like "garnet-hued sea", "sapphire-hued sea", "burgundy sea", but they all miss on either hue or clarity. "Lee-dark sea" is probably the closest, and hits the wine idea.