OK, one more time.
Newton I concerns inertia (state of rest or state of motion) and Newton II covers momentum. Sorry, you are wishing away the physics by saying the momentum is the same regardless of the wind!!
Newton's first law is a special case of the second law, which says that the rate of change of momentum of a body is proportional to the net force on it. No force, no change in momentum.
When you talk, rather vaguely, about a body "overcoming its inertia", you mean changing its momentum, which requires a force, according to Newton's second law.
We all agree that the momentum with 60kt headwind/60KIAS is ZERO. If the wind was zero the aircrafts momentum would be the mass X TAS (groundspeed). These are clearly different situations!!!
In the former case (with the headwind) the change in momentum in a turn downwind is zero to 2 X mass X TAS, i.e. - 2 X mass X TAS.
In the latter case (still air) the change in momentum in a turn similar 180 degree turn is mass X TAS to - mass X TAS, i.e. - 2 X mass X TAS.
What the aircraft has to do to "overcome its inertia" in each case is to change its momentum by 2 X mass X TAS. This requires the same aerodynamic forces.
Physics works in any inertial frame of reference. You can consider the problem in a reference frame moving with a jet on an airway flying overhead if you like. The absolute values of momentum are different but the change in momentum is the same. There is no absolute value of momentum, the only thing relevant to Newtonian physics is its
change.