So, I saw a Zed in a 2v1 lane and...
Teambuilder. My friend goes midlane Zed against Syndra. I go botlane as Thresh against a Zed alone ( I had Jinx adc with me in lane ofc). Both Zeds are platinum, so while they aren't competitive material, they also aren't total trash.
Either my platinum friend is complete garbage, or the enemy Zed was underrated, because througout the lanephase botlane Zed managed to stay within a 15 cs range of the midlaner Zed , while harassed, costantly under 50% health. Keeping him under his turret doesn't work,since his passive works well at execute minion (add shuriken if the turret is going to steal). keeping him frozen in lane doesn't work, he just sends the shadow against caster minions, and shadows shuriken on melee minions.
Now, I always said that Zed had a too easy farm for a midlaner, but I wouldn't have expected that he could be proficient also in a 2v1 scenario. And we aren't talking about a perfect Zed who missed all skillshots, he got grabbed , flayed andzapped (dodged traps tho). Sure, high skillcap, but the farm is easy mode.
bot lane (i don't remember what i was against i think it was thresh support though)