The French have classes.

1. Germany and France stipulate that public education should use the mother tongue until the postgraduate stage. So it must be mother tongue communication.

2. 100 years ago? I don't know because I haven't verified it. But I feel that from my understanding of the French, their stubbornness determines that they must use their mother tongue.

The French know even less English. Personally, I feel that one in ten French people in Paris can speak English. Germans know more English, maybe more than half. But their pronunciation also sounds terrible. So it is unrealistic for you to expect any two German lawyers to communicate in English.