No, that’s not possible (and a bad idea anyway).
C# has a clearly designed specification that defines all language constructs, and such “translations” are not part of it. It would be possible to create a computer language with such a feature, but the impact would be huge:
- the list of keywords would increase for each “language”(in your example,
Si
has be a reserverd keyword). - learning the language would be harder.
- the majority of users of the language would not be able to read your code (just think about the fact that each basic type has multiple names.
- as a professional developer, you would probably still need to learn the english version, and learning the french version first would be wasted time.
- it would be much harder to write a compiler for such a language (harder == needs more time == costs more money), for very little gain.
So I would not be surprised to see a esoteric fun computer language with such a feature; but a production ready mainstream language? No.