"Blend of La- and Shanna"
The name Lashanna is commonly a female name from the "American" origin.
Lashanna is a twentieth-century American formation made from the prefix La- attached to the given name Shanna. The La- prefix is a recognisable element in American naming of the period, and the name first appears in United States birth records in 1968. Nothing in the records points to an earlier or non-English source for this particular spelling.
The pronunciation of Lashanna is luh-SHAN-uh.