There is perhaps a male name oh joanne. However it is certainly not a conventional one. Nor is it a conventional female one.
Joanne (capitalised as a proper noun) is generally recognised as a female name, though that too is convention.
It is considered a boy's name. Joanne /Joanna or Josephina are girl version.
Joanne Engelhardt's birth name is Joanne Osman.
Joanne Brooks's birth name is Joanne Miller.
Joanne Quintas's birth name is Joanne Santos.
Joanne Greenberg's birth name is Joanne Goldenberg.
Joanne Whalley's birth name is Whalley, Joanne.
Joanne Carner's birth name is JoAnne Gunderson.
Joanne Linville's birth name is Beverly Joanne Linville.
Joanne Rio's birth name is Joanne Gloria Rotunno.
Joanne Rubino's birth name is Rubino, Joanne Lee.
Joanne Ruscella's birth name is Joanne Lynn Clark.
Joanne Jonas's birth name is Joanne Rose Jonas.