Cloud's Advent Children outfit did appear in the games like Kingdom Hearts 2, Dissidia Final Fantasy, etc. If you look at alot of the content from anime/movie stuff, they have appeared in the games first before being added to Smash Bros. Like not were in the games first, but appeared in games before appearing in Smash Bros. Like Ash-Greninja appeared in Sun & Moon first before being added to Smash Bros. Or the Advent Children remixes are remixes of music tracks that appeared in the game Final Fantasy VII first.
They’re still non-game content in the first place. Which is why the distinction is extremely arbitrary in order to make rules up to justify a poor terminology. Especially when it doesn’t even care if it’s first party or not. The term loses meaning when it’s not a legitimate offshoot of 3rd party anymore. The entire point behind it was being another shorter way to say “non-game 3rd party.”
If it can’t even mean that? It stopped being useful in a legitimate fashion.
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So I took the time to see how it's used or even documented. Smash Wiki doesn't even acknowledge it. You'd think something so prevalent would be in Urban Dictionary, right? Nope. TVTropes, which has tons of lowkey nicknames doesn't even have it listed, even when it slightly acknowledges the term(and that makes sense. It's not really a heavily used term in the first place. It has to hard explain the term because it's completely obtuse. The funny rule about a fan nickname even there is that it needs to have a clear cut definition. It doesn't). GameFAQs is funny, because even when asked, they have multiple answers. That's because it's not a catch-all term either. Much of the time, it does refer to a character not from a video game. It's rarely used as "non-video game franchise", and isn't really some accepted fan term either. It's a minor one that didn't much catch on because nobody knew what it actually refers to. General fan nicknames of any franchise are very easy for said fandom to recognize what they actually mean. They're easy to define. ...This one isn't. That's a good sign it doesn't actually work.
Besides, the original Motion Sensor Bomb is directly based upon GoldenEye 007, a definite non-game franchise first, so this idea it matters? It really doesn't. That's not even counting how it still appears in Brawl's Chronicle, showing Sakurai has no issues in general noting it. It's easy to see why James Bond was even looked at. Content from his franchise was already in Smash(though once Brawl came around, they decided to stop referencing GoldenEye 007's design). The whole "they didn't originate from a video game" pretty clearly is about licensing at that point too, as it's been made clear they want characters from game franchises too. Which is fine, since it's simply a licensing nightmare even moreso than other 3rd parties are. Especially with tons of voice actors, any book creators, etc.
Basically? Even if you want to subscribe to the silly term, Smash already had fourth party content in the first place, from the first game alone. Which contradicts the point, doesn't it? That 4th party is basically another form of 3rd party, as non-video game franchises can't be owned by Nintendo in this context, otherwise they're already 1st party. Starting to see why it's confusing? That's because it is. The term doesn't make any sense, especially as it's very easy for Nintendo to add their own content that didn't originate in a video game, which still makes it a non-video game franchise. And it'd still be 1st party. Though as I said below, the actual proper usage of "party" in video games is about licensing and ownership. It's never legitimately been about origins at all, and that just makes it hyper complicated for anyone to discuss when 1st and 3rd party are highly simple and more useful terms for everyone involved.
