I know it's mostly a dead point by now, but it's an interesting topic and I was too busy to answer yesterday, so...
I dunno, the one time I looked at what a League of Legends character could add to the game I was quite intrigued. If most or all of the candidates are like that I think the discussion could be quite fun.
Yeah, League has a lot of interesting playstyles and choices, but at the same time, out of all 150 options, discussion would probably default to the same dozen or so after about a week. This is due to a multitude of factors:
Some characters have abilities that can't be directly translated into Smash or even don`t make too much sense as part of a platform fighter, but at the same time are a core part of their identity/playstyle.
Ex:
Cho'Gath has an ability where he literally eats a target whole, gaining extra health and
growing bigger every time, to the point where a good Cho player will be almost as wide as the lane by the time the game ends.
Ekko has time manipulation as a core part of his identity, including having afterimages that track his movements and an ability that reverses his position to 4 seconds prior and heals him.
...And of course,
Teemo becomes invisible if he stands still for 1.5 seconds. Which can be really fun in LoL, but considering you can't move or attack, would be cumbersome at best in Smash and useless at worst.
And then again, some just... aren't that popular to work as a face of League.
Taliyah and
Aurelion Sol come to mind (the latter being a particularly jarring example when you consider he's basically God in the League lore).
So by the end of week 1, there's a good chance we would default to just the most popular characters, like Ahri, Lux, Jinx and Ryze.
That's true, the game has a lot of very interesting choices.
3BitSaurus
is more familiar with the game and its characters generally than I am, but that game's figureheads are pretty diverse and have different mechanics to them that can work well with Smash. Riot would probably be willing to help since
they've made a Smash mod in the past.
I'm just thinking the general reaction would likely be negative -
especially within the Japanese community, where LoL is niché and there are likely to be some complaints that Nintendo "sold out to Chinese and Korean interests". Also: no matter which forums we're talking about - Western, Chinese, Korean, whatever - the guessing game would likely wear itself out quickly because it'd likely devolve into "X is going to get in because Sakurai usually prefers the mascot", "Nuh uh, Y would get in since that character's got the most iconic passive!" etc.
To be fair: even if Japan has the
third smallest server by ranked population these days, if we use the "over 100 million users" statistics from 2017 and do some math, that's still roughly over 700.000 players. Not too crazy, but it's also better than a lot of western games have done in Japan. It's why many speculate that League isn't as popular in Japan not because of the game itself, but rather because it's specifically tied to PC (which is notoriously small over there), plus the fact that Riot never really bother to advertise much in Japan.
I'm keeping an eye on how the japanese playerbase changes when LoL comes to mobile and console - I think it's almost certain we'll see some growth, however small.