I want my old ow back

why cant we have a mode where all the old heros are the same…, i want my old mercy ult, i want my old hanzo back is suck playing this game, if i cant use them becasue you only caring of overwatch league i wanna see what you guys going do with overwatch league if no one plays the game it self, am not asking for comp am not asking for quick play, all what am asking is just weekly stupid game mode, where i can have my old heros that i trurly enjoyed playing with.