I have a large Richard Family tree in my database. I am a native of Ville Platte, Evangeline Parish, Louisiana. I doubt we have a connection, but the following is what I know about Richards in Louisiana.
Mathurin Richard b. 1743 in Grand Pre, Acadia s/o Paul Richard and Madeleine LeBlanc d. 24 Dec in St. Landry Parish, Louisiana, bur. St. Landry Catholic Church, Opelousas, Louisiana
As far as I can tell, he is the first of his family to come to Louisiana.
I have traced Mathurin's family back to Andre Richard, b. 20 Nov 1600 in Saint Ange, Sene, et Marne, France. Andre died 21 May 1861 in Port Royal, Nova Scotia, L'Acadie Canada
Mathurin's death information comes from Southwest Louisiana Records by Rev. Donald J. Hébert. Earlier information comes from other researchers that I found in various publications.