Honestly speaking in a little spotty on the idea of another Pass as is, much less 2-just with the current one+ Mii skins we're shelling a little over 100 bucks as is for the full thing.
The line between "Sound business model" and "Microtransaction Hell" (Metal Gear Survive, Artifact) is sometimes a fine one, mind. I'm pretty sure Nintendo and most other companies (like Activison with Crash Team Racing) wouldn't be this bold weren't it for League's and TF2 / CSGO / Dota 2's models basically substaining those games for years.
For example - Valve releases a "Battle Pass" in time for every International (Dota 2's world championship, held anually) since 2013. A couple things to note:
A) 25 % of the proceeding go to the International's price pool.
B) The "Battle Pass" contains loads of items, skins etc. - including exclusives - for seemingly every character and thing in the game. Those items - and sometimes the chance to gamble for more exclusive items (at no further cost, but still) - are rewarded as the Battle Pass is leveled up. Via playing the game, getting achievements etc. Or, you guessed it, spending more money on it. All items are completely cosmetic - sometimes include special particle effects etc.
C) Oh, and the Lvl 1 Battle Pass is a $10 thing, There are $30 and $45 variants (that skips directly to level 50 and 100 respectively, with all the rewards up to those respective points automatically granted). The rewards go up to level 2000, with repeating rewards starting to happen after level 300.
It sounds like Microtransaction Hell at first glance. And guess what? It's a major success each and every year. Buying everything in Dota 2, League etc. is about as likely as buying everything in Train Simulator:
But fans still throw money eagerly at those things. The intent's not to have people buy everything, but enough to cause dollar sign eyes among corporate heads. Of course people do have a point when they consider the model unfair instead of fair - again, Metal Gear Survive, Artifact and judging by Cadiccarus' reactions, Crash Team Racing post-launch. And both Konami and Valve are still aching after MGS / Artifact's failures; one could view Snake's return and the Belmonts' addition as a way to distract from the now dead Survive.
Also, I wouldn't be surprised if Nintendo goes for a second Fighter Pass. The Battle Pass returns each year, by comparision the theoretical Fighter Pass 2 would come out around March 2020 at the absolute earliest - at least 15 months after Fighter Pass 1 (December 2018 alongside the base game). While Smash is different from F2P MOBAs, I wouldn't be surprised if Nintendo at least looked at how other fighting games do their DLC before doing a FP2 or not. They might have looked at the MOBAs microtransaction structures too, at least to look at how much people tolerate or consider a fair trade off for their money.
