One option would be to see if there are any bitcoin ATMs left in France that do not ask for KYC. Most in Europe already ask for it but according to MiCA they have until September at the latest. With no kyc BATM you find you can withdraw up to 995€ a day, every day until the end of August. Obviously, what should be done is to declare these transactions even if they were without kyc, but people use them to avoid declaring them. That's why politicians have imposed the kyc, so that taxes don't slip through the cracks.