Really torn with this film. I loved the idea, a clever take on the time travel genre without having to use time travel tropes.
The thing that always keeps me coming back for Les Cousins films are the iconic lines or themes (I re-watched your 2014 entry and couldn't help singing along).
For me, this lacked that, and whilst well-shot and acted, I feel that the storyline lets you down, premise was good more than executioon I feel.
Might just make finals from the films that I have seen, best of luck anyway!