Even if it wasn’t known as a popular term until 1930, I’m willing to accept it being used in my imaginary, miniature war since it seems to fit so well.
As to negative connotations, that’s sort of the point: An Englishman tagged with ‘plucky’ or a Frenchman accused of having ‘elan’ would see it as a compliment – but in game usage it is a hollow quality without the talent to back it up. ‘Moxie’ appears to be similar.
Of course, this puts ‘hallschmerzen’ into question: would a German (in general) see pursuit of medals/glory as a bad thing? If not then the term works.