It might be “fine”, but I’d think this would be one of those things that any caring mother wouldn’t do just in case. Call me a control freak, but I’d personally throw a fit if I saw my hypothetical wife drinking and breastfeeding. At what point would a woman even sit down with a glass of wine and be sipping it while breastfeeding anyway? Is that enjoyable? Is it some past time I don’t know about? Like, do all the girls get together for girls night and kill a few bottles of Pino Gritio and breast feed a little? Just seems rather absurd. An there’s no way this doesn’t get a baby drunk.
Side note: If this means that later in life the child will have a higher alcohol tolerance, then in that case all women should be doing it. I wish my mother would’ve done that.