Loveless aka Nelyubov is a Russian movie that won the Jury prize at Cannes and has quite a bit of nudity from its two female leads.
At 13 minutes, Maryana Spivak shows part of her ass as she puts her pants on after going potty. Then at 26 minutes, Maryana shows her bush briefly and more ass from the side as she is about to get waxed. Lastly, around 39 minutes in, Maryana is naked while having sex. The scene is super dark though so you can’t really see much. Maryana then gets up and walks to the window giving us a dark view of her ass. Maryana is then in the kitchen and we see her full frontal nude as she walks back to the bed. Maryana then shows more of her ass as she is on the bed. Finally, Maryana shows her breasts and bush briefly as she gets on top of her lover. The scene ends at around 47 minutes so there is almost 8 continuous minutes of Maryana naked but with bad lighting.
At 32 minutes, Marina Vasilyeva also has a super dark sex scene where we see her breasts. At 107 minutes, Marina is shown in her underwear from behind in the bathroom. Marina then removes her bra and we see her right breast briefly. Marina’s character is visibly pregnant in both of these scenes.