This is a simple python script to remove nation livery restrictions on ALL modules you have installed (Official modules, third party modules, downloaded modules).
Bugs: Some aircraft work with compacted files, I do not want to get into that right now, so it doesn't work with them (Hornet is one of those aircraft). Luckly Bobick2002 made some files you can replace: https://www.digitalcombatsimulator.com/en/files/3300694/
Check https://github.com/LombardiDaniel/dcs-livery-unlocker for more info.