A few people are working on add-on solutions for that, but we should likely see what’s up after the next update on April 15.
It’s supposed to bring French airline liveries and even some French manufactured aircraft into the AI fold, so I imagine it’ll come with some changes to how AI traffic works in general.
Otherwise, I can’t see how they could avoid having airports in Tokyo full of French aircraft if you put the parked traffic to any more than zero.
I guess seeing how the update changes things is pretty much the starting block to see what else needs to be done about it. That’s one of the reasons why I’m eager to read the patch notes.
PS: the A320 are there because the parked aircraft setting will cause the sim to randomly select liveries/aircraft you have in your community folder and sprinkle them on the aprons. It has nothing to do with real traffic.