Notteke Explet's is an anime made by Naomi Iwata of Gregory Horror Show and Midnight Horror School fame. There's NO footage of it available online, just screenshots.
Here's the synopsis from here: "Tsubasa always believed that the railway tracks continued on forever. However, every track, like every story book, does come to an end. Tsubasa never imagined that at the end of that dark tunnel they weren't supposed to venture into lay the end of the tracks and the foretelling of a sad end to their story. But, he also finds hope and a way to the outer world that leads to other books and whole new worlds. Unwilling to accept that their fate is predetermined, Tsubasa and his train friends jump from their story book and travel to others in search of the tracks that continue on to the future and a happy ending. But it won’t be easy because the Black Explet's, the bringer of all sad endings, is always hot on their trail. Story book stories are no longer static in this world and there is no end to the possibilities and fun in the search for hope and a happy ending!"
I REALLY want this show to be found online, it sounds so cool!
I know this subject here has been here since 2018. Before I begin, I'd like to say that I have been doing a little digging myself into this show, again, I saw some still images/screenshots of the show and I found more images. I came across a tumblr user who had a DVD or two (I'm assuming they have two volumes). From what I've remember, I heard that the show has 2 volumes. But I didn't have a tumblr account, I can however visit the site as a guest??
I've came across a YouTube channel that DID some walkthrough of the official website for the show before flash eol. And then I came across a comment that linked to a document that had all the episodes. There are two additional videos in said document (one had every episode from volume one, and the other had all episodes from volume two) I actually did see the first episode, and it was interesting to describe it the best I can. Sadly there are no subtitles and i don't know a single thing about Japanese. So I guess you're gonna have to find someone that knows Japanese.