Maybe some company will manage with a perfunctory stop in Perpignan?
I suspect there is not a lot of track capacity across the Pyrenees, though, which would mean the sleeper train would have to get in before the morning expresses start.
https://www.youtube.com/watch?v=Bq0aA9RZ1ls
The train passes through France non stop. Along the way, around 2AM, a single carriage decouples from the end and smoothly glides into a Paris terminal, where it functions as a de facto hotel room for the night as guests won't be kicked out until morning. Will anyone use it? IDK. But it does satisfy the requirement of stopping in France.
There are several ways to work around that though, and I think this will happen in the reasonably near future.
The problem with Spain is that the majority of the network has non-standard gauge (approximately everything except the AVE high speed trains).