Beloved Normand, "what say you" rather than "what do you say" may be used in a courtroom, for instance. A judge, in asking for a verdict, might well say: "What say you?"

To the best of my knowledge, in all other situations, it would be: "What do you say?"

We would never say: "What think you?" or "What love you?"

If this doesn't work in French, of course, use what does work. It would be perfectly fine for you to translate the expression as: "What do you say..."

Now let me see what I can discover what I can find on Google.

Urban Dictionary says:

What say you? An archaic English phrase that is still used in a legal and governmental context. It is used to ask for a verdict or a vote. This phrase is sometimes used in everyday conversation with the same meaning - usually with the intent of seeming formal, stylish, or unusual.

Normand, there are so many unusual usages of English. I don't know how anyone can learn them all. For someone like me who has spoken and read English all my life, I just know this expression without even thinking anything of it.

I have heard that English is very difficult to learn because there are so many exceptions that just have to be learned one by one whereas other languages are more consistent.

How are you doing in learning Chinese, by the way?

Apologies for not seeing your question sooner, dear friend. And, thank you, too, dear Luus for alerting me.

Love, Gloria