Well that stupid rule from Kwami Buster is moot now. Marinette is officially Guardian and Fu was put on a bus. So it's gonna be up to Marinette to decide what to do if they reveal themselves to each other. There's no way Marinette can give up her own Miraculous at least, she's Guardian now!
~
marinette: [corrupted by an akuma victim's influence] CHAT NOIR I AM GONNA TAKE YOU OUT
chat: if you wanted to go out on a date with me all you had to do was ask
marinette: how is it that I'm the one corrupted by an akuma and you're still more terrible than I am
chat: good to know you're still in there, marinette