Yeah, but nothing is stopping them from re-releasing Amiibos without it being related to Smash though. And the fact that amiibo's being rereleased around the time of them relating to game/Smash announcements is a pretty loose thing. I agree that amiibo release dates indicate the expected time of the next fighter's release, but other than that they haven't really consistently predicted the reveal of future characters (if at all). I don't really remember all the amiibo restocks that have happened so far either, so I don't know when Zelda and Xenoblade amiibo's were restocked. But that's just me, you may know more on that. In my opinion, if they really were pairing amiibo's for characters; then something like K. Rool would have been also saved for Dixie rather than getting reprinted earlier.
Even if it's just a semiclone, it'll still be a good chunk of work considering that the team is probably quite a bit smaller than base game (even if it's ideally the size of FP1). Semiclones still nedd a lot of new animations, and I think pushing certain characters like Waluigi as a semiclone would be weird to do (he really is nothing like Luigi and in terms of size would be pretty different, though they made Dark Samus a semiclone so...). Now we have no information on how much time semiclones take, but I still think creating all the animations, testing for bugs/glitches, balancing likely take a month minimum (If we think 4 months is the right amount of time for a full blown character).
I also think it's a pretty big double standard for saying a full blown Mii costume is a consolation prize, and then saying something like an AT will get upgraded considering those are also consolation prizes. Waluigi and Mii costumes like Rex, Springman, Viridi are in pretty much the exact same position as neither an AT or a Mii costume has been upgraded in the exact same game. I don't really think there's enough evidence to say that base Mii Costumes are off the table yet AT's are not. Even if Waluigi has been heard a lot by insiders, he could totally just end up being leakbait for Geno (or maybe Geno is leakbait for him). I just don't think you can say that mii costumes are fully deconfirmed yet AT's are not with a straight face. Besides I don't really think AT's OR Base mii costumes deconfirm, and they definitely only did for Base content + Planned. Reminder that Sakurai even said that originally spirits were a way to represent characters in a way that wasn't fighters AKA a consolation prize, AT's/Mii costumes were either just higher priority or easier to get the rights of/port back from Smash 4.
In regards to Sakurai saying he doesn't like to add characters he has created, I don't really remember that. And it's not like Sakurai has no qualms with adding characters he had created in the likes of Smash 4 with Dark Pit for example (and while Palutena isn't completely created by him, he did create the modern representation of the design, and chances are Medusa would be in the exact same position), And while a Retro rep is decently likely (Hero/Terry esque), there are a dozen of other choices comparatively (the WTF character was Pirahna Plant, sure it isn't "Retro" but it definitely is WTF). Sakurai even directly compared it to the likes of Game and Watch, ROB, and Duck Hunt.
And on top of that Lolo and Lala weren't even in the spirit list, so clearly they weren't high in their list for representation in base (even as spirits). So unless Lolo has some amazing evidence backing him up by insiders, which I doubt. I can't really see a character like him getting in. Like I said before, there are a bunch of other "retro" characters they could end up adding, some first party and some third party.
Again overall I still think that even an echo/semi clone pass isn't happening. It's going to be these 6 unique characters, and we're done. There's far more evidence backing this up, comparatively. Suggesting that there are "bonus" characters happening right now, even if it's just semiclones, is just giving me Grinch leak flashbacks; where people were saying we have a good chunk of fighters left because Sakurai likes to defy expectations and it turned out we just had 2 left.