It's all steady cam. Actually one character makes a disparaging comment about the excessive use of shaky-cam in movies for stylistic reasons, which I appreciated!
There is no gaslighting in the sense of a person coming to doubt their own sanity because of abuse. However, the film does revolve around a woman who has toxic relationships with several of the people around her, especially her daughter. There's lying, manipulation, and drama about people remembering different versions of past events. It's not an overly heavy film but take care if these may be triggers for you.
Nobody dies during the film. Years before the events of the film, Juliette Binoche's character suffered the loss of a woman who was a mother-like figure to her growing up (we never meet this character). She struggles with this because she was closer to this woman than her actual mother. Also, Fabienne, a famous actor, is acting in a film about a relationship between a woman and her terminally ill mother (though the mother in the film also doesn't die).
Ethan Hawke's character is implied to be an alcoholic in recovery. He states that he is not drinking, but he is repeatedly offered alcohol by other characters, and relapses. It's not a major part of the film as he is a side character but it could still be triggering.
The child in the film is clearly loved and not abused. We learn through dialogue that Juliette Binoche's character had a somewhat troubled childhood due to her mother's self-centred and manipulative personality. Not enough details to know if abuse was involved.