Regardless of if you should or not, could you effectively play LB as a viable ADC? Sure it is not the best idea, but she has her kit (mobility, scouting with ult, and a hard CC) which could work well for the role. Or is the role requirements simply out of the reach of those champions who are not meant to be ADCs meaning no outside champions could work?
Environmentalist1 votesI mean, you could. There are a few champs that people bring into the ADC role, like TF and Thresh. They have their pros (Thresh's E passive, TF's stun) and more, but they lack the stats per level that an ADC would get. I think that's the main reason why you don't see as many super off meta ADC picks.
JavelinJoe1 votesInterestingly, LB has a higher AD max scaling than most ADCs do, though her AS is much lower.
dunder kill1 votesNo. Not as a viable one at least. Zero AD or AS scaling
SangreDeNoche1 votesThe master tier lb duoing with a diamond annie support who single-handedly hard carried the fuck out of a game with golds and plats I was in says yes.
(They were something like 30 of the 35 kills the enemy got on us that game. Their allies really had nothing to do but push towers since we were dead so often.)
Proxy3451 votesIf you land that tether then you can build anything and still roflstomp any ADC lol
Fresh Untilted1 votesBasically, no. And the reason lies in her attack speed, which is on par with tristana, however, tristana has 100% attack speed steroid for free, so that doesn't really compare at all. It's gimmicky , that's all.
Let me tell you a story about how Kennen became an adc back in the day. His attack speed is 0.04 points from being the highest base attack speed in the game, which means that attack speed items stack better on him than any other legitimate adc in the game. His range was also higher than MF's, but now it's the same as MF's, but he doesn't have an attack speed steroid like her, and no AD scalings, so he fell out of favor.
Leblanc has 525 range, compared to MF's and Kennen's 550. Kennen also has a pretty solid stun option that is a LOT easier to hit. I'd still put Kennen toplane though, due to how he can bully a lot of melee laners there with Aery. I sometimes play around with Kennen top building BOTRK, Runaan's and frozen mallet, and it's great fun. Leblanc in comparison, would be like saying that Ashe could be a good AP carry because of her ultimate, and how she can apply Luden's with her W. That doesn't make her viable.
JavelinJoe1 votesLeblanc in comparison, would be like saying that Ashe could be a good AP carry because of her ultimate, and how she can apply Luden's with her W. That doesn't make her viable.
I get what you are saying here. But attack speed could be made up for with the correct runes somewhat. That being said, I feel that having a hard cc ability as early as level 1, or a good movement ability gives her a lot of advantage over other ADCs. That could somewhat make up for the attack range difference if used right too.
She has a low attack speed stat though, so like you said, not so good with those items per say. But what about a burst ADC style game play? She actually has the highest base AD maximum of almost every ADC besides Jhin I think. 
for a build. Pop in, AA, pop out, repeat.
Fresh Untilted1 votesTake out the steraks and replace it with rapid fire cannon, I may be able to get on board with a gimmicky build. Would hardly be meta though. Would also still be better in midlane than as an adc.
JavelinJoe1 votesI added Sterak's simply because of the +50% base AD. LB can get up to 114.4 base AD at level 18. So adding an additional 67.2 ad is nice , plus the shield could help as a bonus. I checked the wiki and Jhin and Kalista are the only "true ADCs" who have higher max base AD than her (129 and 115 respectively). The others are around 106/107 or in case of MF, a measly 71. And it adds to the burst from Trinity Force. This was my reasoning for including it.
RFC would work too, but as you said, she scales poorly with Attack Speed. While 80% crit would be great, and the passive hits fairly hard too (not to mention more often with it), but you waste the gold on the added attack speed imo since you are more or less looking to burst with maybe 1 to 2 autos ideally.