I use Dark Harvest in this example to help deal with late game Urgot but typically Electrocute is my go to.
Play Video

https://www.youtube.com/watch?v=dfSKSC4i9IE

This is going to be my first guide and it is about a particular off-meta pick for a support. Lee Sin can be and extremely lethal killer when fed so the idea of playing him in a passive roll such as support is typically not seen as viable.

His kit allows him to punish enemies that are attempting to retreat with low health as well as apply a small shield to their carry while repelling champs with his ult in case of any ganks from the enemy JG or plays by the opposing laners. Though very situational Lee's kit fills many needs as a support and can still snowball well without taking all the carry's kills.

Lee Sin isn't known for taking a passive roll during the early game and many people can carry a game by using him as a laner. But, something I've come to notice is that he can be extremely useful as a support when the enemy bot consists of one or both of the enemy players being mage type enemies (Lux, Veigar, Soraka, etc). His ability to dash to an escaping enemy that starts with a lower amount of health and defense and potentially push them back towards the bot laner with his R can lead to an early snowball that is hard to push back against. Along with his ability to shield his ally this makes him a situational viable support pick.

Lee doesn't lane well against champs such as Blitz, Pyke, and Thresh that can pull him out of position so he is not going to do well outside of certain enemy team comps. Even if the enemy bot meets the conditions above Lee may still not be viable depending on who he is laning with as a partner. The best option are dash or follow up champs such as Lucian, Vayne, Tristana, Kaisa, Ezreal, or even Jhin if they are able to land their stun. Other possible compatible champs are longer ranged champs with the ability to keep hitting the enemy as they attempt to fall back. These are champs such as Caitlyn, Ashe, Jinx, Varus, or Twitch. I wouldn't recommend playing Lee sin with and AP or Melee bot laners unless they have a CC that combos well with Lee's kit.

Electrocute can help deal more damage early to get your lane snowballing but if you are going against champs that focus late game Dark Harvest is still a good choice even after the nerfs.
Bone Plating helps mitigate a lot of early game damage from mage champs and can help survivability when diving early game.

Though supports typically pack ignite or exhaust this build is much better suited to you using heal at the right moment, whether that be dashing onto you carry with your W then popping your heal to keep them alive or just a little more life to help finish off an enemy that is on low health.

Your support item is going to be Ancient Coin, this will allow you to stay back from poke damage most of the time as well as restore energy while in lane more efficiently.

Your first build should be Trinity force, the extra damage from sheen pairs very well with your Q dash and gives you some extra attack speed.

Your boots are dependent on the games progression, most of the time Merc Treads are going to be your go to but Ninja Tabi are useful when fighting against champs like Vayne or lucian.

Most of the time you will build into Dead Man's Plate for your first defensive item. Merc Treads with keep AP damage down for the early to mid game and the charge from the plate can get you moving.

At this point if you should build Maw for a little extra damage and more MR but if you are ahead and the enemy's AP is still relatively low you could go cleaver for some more power and health.

From here use your discretion to decide what best suits your needs, if your team needs more tankiness go armor, if your team isn't able to kill fast enough in team fights build to kill their damage.