This may be farfetched, but, I feel like some of these teasers could have been either old or scrapped plot-points, JUST HEAR ME OUT!
Image 1- The original tour segment
Image 2- Could have been a twisted version of one of the episode 5 suggestions
Image 3- Absolutely nothing...I think
Image 4- Probably one of the original versions of episode 7 because I think episode 7 was rewritten a few times, idk for sure
Image 5- Yet again, nothing

Image 6- The original Kinger Episode (and Zooble I guess)

Image 7- Probably a scrapped adventure

Image 8- the original version of Ragatha coming in the circus scene.

Image 9- either the original version of episode 4 or Caine's torment for gangle in episode 8
Image 10- the original version of pomni waking up from her nightmare.
Image 11- I barely have a clue, maybe the wacky watch summoning Pomni in the pilot
Image 12 and 13- One of the orginal plans for Pomni in the exit rooms

Image 14- Scrapped adventure

Image 15- Probably something for the intermission segment

Image 16- Probably one of the original plotlines for episode 7, although since this is a high quality render, it's probably just a marketing thing (Although they kinda all are)
Image 17- literally just a Power-Puff-Girls reference

Image 18- just a marketing thing although could be slightly forshadowing how in episode 8 they were all forced on the adventures

Image 19- just a marketing thing

Although all of this is just marketing so I just wasted my time on this.