Zed falls off late game,
and
removes literally half his damage.
Annie on the other hand is a bit harder to deal with. You can't really stop her from flashing and casting Tibbers unless you kill her first with poke.
Generally, try not to group closely when there is an Annie on the enemy team. She is practically immune to assassinations due to her stun, but her medium range leaves her vulnerable to champions such as
. Of course, engaging on her first is also an option if you have champions such as
or
.
If Annie gets ahead though, it is GG. She is going to take out the people she combos before the stuns wear off, so the fights will never be in your favor.
BTW, Cleanse does work on Annie Stun and Death Mark.