Helicopter123 - the answer to your original question
if the helicopter can hover OGE at 4000ft with 5000lbs maximum gross weight under 0 wind condition, what if we got 10kts headwind, can we hover OGE at same level with more than 5000lbs gross weight
is
no, unless, as geoffers says, you have the graphs in your RFM specifying wind effect.
Does more wind give you free performance? Yes, unless you use that performance to exceed any other RFM limitations - Max AUM for example.