[2023] [PS5] Game language can’t be changed

I know nothing about how such things are done on consoles I'm afraid. When you start the game do you see a Paradox launcher like you do on PCs?

If so there's launcher and game language choices - quite separate.  

So I take it you do NOT see a game launcher? As that is where this would be set on a PC.

If there is no option to change language in the game, I would have thought it would use the PS5's language - but I guess that is not in French, from what you say?

If not, I think you'll need to contact PSN and swap the French copy for an English one.