A little analysis:
Just wanna say that people should have a little more faith in Loz18 and his statements about Skull Kid and Isaac. Most importantly, if he was trolling, he has not continued his troll or baited attention on Twitter, nor anywhere else. I know for a fact he still talks to a few people he trusts on a private discord, but they have nothing to do with leaks because he has leaked everything he has right now, or has leaked what he is comfortable leaking. Many of us in a separate discord server have come to the conclusion, based in his tweets he deleted and his many PMs to users about things, that he is involved with Nintendo/Bandai/Smash on an information/script level.
This is why he leaked the E3 direct with 100% accuracy and the August direct with about 80%. The reason for his accuracy would be that he only sees the raw transcript from the directs to confirm info (he has confirmed this to several users about seeing "scripts of info" in several PMs I've seen), so when he says he has to be careful about leaking things, he doesn't know if said character is PLAYABLE, only that they are in the game (because text script may or may not reveal that info). However, this partially changed with K. Rool being revealed.
Here is an example PM in a thread (post #63) about him knowing of K. Rool before the august direct And ALSO mentioning Skull Kid in text similar to how K. Rool was revealed. (check the time of the PM)
https://gamefaqs.gamespot.com/boards/234547-super-smash-bros-ultimate/76883130?page=6
In future comments, he has talked about how the info he had seen on Skull Kid (1 of 2 characters he at least knows about, but is much more sure of Skull Kid at the time) was similar to how knew about K. Rool, but never said anything because he wasn't sure if K. Rool was playable (at least that's what I felt he was getting at, at the time)
Fast forward to his 12 year old Gamefaqs account getting closed. Right before, he leaked that a November direct is happening (specifically a smash one). While it may seem obvious, if you have been following me this whole time, it's likely he got a hold of material related to November's direct.
Then, he makes a Twitter account, proceeds to hint at skull kid and now even Isaac. Remember, Loz a few weeks before this specified that there were 2 other characters after K. Rool he has an idea of. He figured one was Skull Kid based in the script. Over time, he seems to have figured the other was Isaac (but has since deleted the few tweets about his excitement for obvious reasons). After this, he tells people that we'll be happy and that Nintendo is listening. 0 troll attempts, just leaves it at that. He has since not posted for over a week there.
I do however know he is still active with other people from Twitter and in a private discord server. Unfortunately, I can't post this info as proof because it trespasses their privacy and what I've promised them, so there is info I must keep to myself. I do know for a fact he has dropped the Loz18 name for something else and is just casually talking with people now however.
So we'll see about how reliable he is in the future, but if Loz is a fraud, I'll be right there with you. I personally have always liked Isaac and I made this post because I want to give Isaac fans some hope. This is the biggest evidence we have towards his inclusion. Perhaps isaac (and Skull kid) have something to do the November direct, or perhaps earlier. But I personally believe they are here and exist. I personally believe Loz and Vergeben has 2 parts to a bigger puzzle about the roster.
If you trust Loz and believe in what I'm getting at, our Golden boy should be in the game. If not, that is okay too. If hes a fake, then at least it was fun speculating with everyone! Just some piece of mind for all of you
Tl;dr: Loz's paper trail is way too slow, precise and methodical to be a troll. He does not post enough to bait attention. If you believe his posts about Skull Kid and Isaac, realize he has not leaked anymore beyond that, and has so far only mentioned knowing of 2 other characters (and has ONLY ever mentioned those 2) aside from K Rool in several of his posts on Gamefaqs.