My response is this: …not if I can help it! :3 What a boring prospect for the world. It amazes me that esperanto is so seldom considered as a viable solution. It allows both regional dialects to live on, and prevents a divergent evolution of the lingua franca (which would defeat the purpose). Esperanto is standardized for long term global unity, unlike french, and certainly unlike english. If the question is wheter it’s possible to introduce such a language to an unsuspecting population: I invite you to look at the history of Hebrew.
If the question is whether it’s possible to keep esperanto and people’s mother tongue separate, we could observe how arabic is used: it’s no one’s mother tongue as such, but it’s used for international communication.
Esperanto is worth a serious chunk of attention, and has been thought through much more thoroughly than you think.