Depending on the English subtitles you get, Lou!'s going to have a considerable amount of profanity in it. The version that's currently on Tubi has a few F-bombs & S-bombs. However, this is more up to creative license on how to translate French words, which don't have that type of analog to swear words. Chances are the language in this would be a lot more tame if translated directly.

Lou's mother drinks a few times during the film. She gets drunk at a party where people are smoking cigars, and one person is using a hookah. Lou's mother accidentally offers a child alcohol, but the child refuses it. It's all framed in a playful, cartoon-ish way.