C++ - Functions calling setters - how to decorate the arguments?

It is my understanding that the current (post-C++11) convention is to write setters with movable types as follows:

void set_a(A a) {
    a_ = std::move(a);
}

What is the best way to write another setter or forwarder function that calls this set_a()? For example:

void set_ab(A a, B b) {
    set_a(std::move(a));  // like this?
    set_b(b);  // or like this?
}

Or:

void do_one(A a) {  // by value? by const ref? by rvalue-ref?
    do_two(a);  // move?
}
void do_two(A a) {
   obj.set_a(a);
}

I don't think std::move() is appropriate here, so how should I write this for efficiency, assuming an optimizing compiler?

Do all these function signatures depend on whether I'm storing the final A object somewhere or not?

Thanks