bidialectal
/ˌbaɪdɪˈæks.təl/Definitions
1. adjective
relating to or involving the use of two dialects of a language.
“The bidialectal speaker’s ability to switch between the two dialects made them a valuable asset in the translation industry.”
2. noun
a person who uses two dialects of a language.
“The bidialectal community in the city was known for its vibrant cultural scene.”