Corswandt
FAFO
I'll ask at the Relógio d'Água website if they're interested. They have a section handling this sort of query.
I knew they'd be the only ones to reply so fast - or maybe at all (thank you, Mr. Carlos Vasconcelos) - but I only got the standard issue boilerplate reply "Thanks for your suggestion, which we will consider." which, granted, is probably all they could say right now. I do believe that, if somebody else had already stepped up (namely Leya's imprint Dom Quixote, which is the publisher of all of Énard's books that got released in PT so far), Relógio d'Água would say so; this means the rights for PT are indeed still available.
Anyways, contemporary French language fiction isn't really Relógio d'Água's thing (was it ever?), even though they're branching off a bit as of late (fantasy, science fiction, Sally Rooney), so I also think this is [/the end].