Team 2 since Sai is a weak link, and team 2 will overpower Kakashi.
Thats why i made the match up, sai isn't a weak link, he has impressive skill feats and his abilities allows team 1 to fly.
His snakes are strong enough to bind yamato and even sakura took some time to tear them up.
In war arc he showed that he can summon the guys out of his book in huge form and with destruction force.
His speed is over yamatos, he was able to react to sasukes attack early shippuden while yamato just stand there. He even showed that he has clone feints against orochimaru ( after oro vs 4 tailed naruto) Sai is an underestimate one.
with Kakashi together team 1 is the team with more skill and tactic why team 2 is the team with more strength.
I myself am not sure how it would end, but I'm leading more to team 1 very high diff.