in my au, itsu was a japanese spy/info soldier (fully trained in comic book fighting skills), in WW2, while logan was also a spy/soldier form canada.
logan had unconventional way of spying-he cross dressed as a pretty woman; he is 4'9 and sort of slim with slightly more androgenous features before the weapon x programme. itsu also cross dresses as a man, but the japanese army is aware of it.
they meet while spying on their enemies(the're on opposite sides), have continued interactions for 5-10ish years during which they have enemies-to-sometimes-briefly-reluctant-allies-to-slowburn-lovers arc, after which they get married at the end of WW2.
none of their sides know what happened b/w them
*(i know history is not correct here :=) )
(let me know your ideas to!)