Good Comment, Alexis!

Referring to Gen: 11:1-10, It seems like God did not want people to have the same language to prevent them to develop ideas such as the one they had to build to the Babel tour.
But at the same time those people could have used "sign language" to communicate to achieve the same result. God did not put that idea in their heart. Does it mean that God did not want the use of "Sign Language" either?
On the other hand, in Romans 10:17 & Luke 11:28, in what language does God expect His word to be heard?

Thank you.
Hyacinthe