Let us pick champions our team have in tornaument mode like ONE FOR ALL

hi, when im playing with my team, or in clash when it was active in EUW, I could not pick for my team , we need xayah but we could not first pick xayah because i was first pick and i didnt had xayah, when we tried put our adc first pick before game start (all team go spec and then join so adc pick first) enemies ban xayah and we like to first pick olaf, but then i didnt had any adc champ to trade with my adc our even pick for him. so why dont let us pick champions our team have like one for all ? not for playing in game just let us trade picks and pick like pro matches .