Theoretically this does already exist in AOE2, where in the custom lobbies players select the same player number/color and have total control of the same "playe

Theoretically this does already exist in AOE2, where in the custom lobbies players select the same player number/color and have total control of the same "player". The backstabbing aspect would be difficult, with lobbies limited to 8 individuals, there would be a max of 4x paired "players" (e.g. pair1 & pair2 vs pair3 & pair4). If teams aren't locked like in FFA diplo matches it turns into a 3v1 (pair1, pair2, & pair3 vs pair4). Unless the game could be modded to support lobbies > 12 or 16, the diplo aspect would be limited.