There is a location hack for the P3, so i dont see why we cant do similar for the Mavic.
As far as i understand, when booted the TX and P3 check to see which region they are in then apply FCC or FC compliance. If its a similar process, consider tinkering to be done to allow full power.
So even if I brought a Mavic in the US once the drone is in EU it will know this via GPS and automatically adjust a CE 4km range setting? so all in all this is a software restriction and not hardware? and once back in the US or out of the EU the drone will regain the FCC 7km settings for range?