Be sure to apply on a very gloss surface...if you don't it would leave large dark marks (much more than with a classic oil paint wash!)
Thanks for the advice. I already noticed it is a bit thick. So I intend to use some thinner prior to applying it.
Concerning the French participation in the Korean war it was known as Bataillon de Corée and the unit crest featured the UN crest so I guess it could be OK for the campaign.