in real life
10 years ago: right foot play right flanks, left foot play left flank
now : right foot play left and left foot play right flanks. Winger 's dribbling is more unpredicted than it was. (example: C. Ronaldo, Ribery, Roben, Messi ...)

in top11
i thinks it is random, even a both leg player play one side better and some player prefere one side but others don't. May be it depends on players, may be it is just random,
an other clearly effect that CD's heights, in real life a 1m70 CD is terrible but in this game, they can have AO Specialiste, can win againts 2m striker in one to one areriel events.