Accent on rosé?

It is a clear error, as it changes the pronunciation. I cannot think of any reason why it should be written with a grave accent as that is meaningless.

Pronunciation. Rosé the wine is pronounced rose-ay. That's an accent aigu (verses grave).

I don't know why you're seeing with grave accent. It's wrong. Unless it's someone's name? Maybe pronounced like Roz.

Ro-zay.

The word is from French. If you don't have the accent, it's pronounced "rose" like the flower, rather than rose-ay the way it is used with wine.

And not sure why you are discussing "accent grave" ( è ) when the word rosé always contains an "accent aigu" ( é ). A grave accent is always top left to bottom right direction. Acute accents are bottom left to top right direction.

Update 2:

The only explanation I can offer you is that someone writing the word rosè instead of the word rosé is doing so because they do not understand the difference. Those accents are what makes the E sound like "AY" instead of closer to an "UH" sound. So they either don't realize they are using the wrong accent symbol, or they are doing it on purpose as an act of trolling.

But I personally have never seen it with the grave accent. In print anywhere except right here in this question.

It's pronounced Rose-A. The little thing over the 'e' indicates that.

without it, it would be just rose and not rosé