You used to be able to convert it in Org/SW at the VP vendors. Im not sure if its still there since none of the vendors use VP anymore. The JP mat vendor still converts to honor.
Just checked Org vendor. The VP vendor no longer sells conquest points for valor.
So is it 100% sure there are no other Vendors for Valor to Conquest? I did write a ticket but it seems like it will take several days for them to answer.
As far as i know this no longer is possible. And you are now meant to actually pvp to earn pvp gear. Not that strange if you ask me, though with the mindset of mop of trying to make people do both more its indeed a bit weird.